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Search for "fluoroalkylation" in Full Text gives 17 result(s) in Beilstein Journal of Organic Chemistry.
Simple synthesis of multi-halogenated alkenes from 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane)
- Yukiko Karuo,
- Atsushi Tarui,
- Kazuyuki Sato,
- Kentaro Kawai and
- Masaaki Omote
Beilstein J. Org. Chem. 2022, 18, 1567–1574, doi:10.3762/bjoc.18.167
- of a steel autoclave at 250 °C [9]. Other halogenated compounds that are not classified as freons have also been used for this type of fluoroalkylation [10][11][12][13]. We recently reported that the reaction of halothane with various phenoxides proceeded smoothly to provide various aryl
Graphical Abstract
Figure 1: Medicines containing a difluoromethylene group.
Scheme 1: Reaction of phenol with polyfluoroalkanes.
Figure 2: Fluoroalkene analogs of some drugs.
Scheme 2: Proposed mechanism.
Scheme 3: Sonogashira cross-coupling reaction of 2a with trimethylsilylacetylene.
Synthetic reactions driven by electron-donor–acceptor (EDA) complexes
- Zhonglie Yang,
- Yutong Liu,
- Kun Cao,
- Xiaobin Zhang,
- Hezhong Jiang and
- Jiahong Li
Beilstein J. Org. Chem. 2021, 17, 771–799, doi:10.3762/bjoc.17.67
- alkyne product 71 initiated by an EDA complex. Mechanism of the synthesis of 2-phenylthiophene derivative 74. Synthesis of allylated product 80 initiated by an EDA complex. Synthesis of trifluoromethyl-substituted alkynyl product 84 initiated by an EDA complex. Synthesis of dearomatized fluoroalkylation
- product 86 initiated by an EDA complex. Mechanism of the synthesis of dearomatized fluoroalkylation product 86. Synthesis of C(sp3)–H allylation product 91 initiated by an EDA complex. Synthesis of perfluoroalkylation product 93 initiated by an EDA complex. Synthesis of spirocyclic indolene derivative 95
Graphical Abstract
Scheme 1: The electron transfer process in EDA complexes.
Scheme 2: Synthesis of benzo[b]phosphorus oxide 3 initiated by an EDA complex.
Scheme 3: Mechanism of the synthesis of quinoxaline derivative 7.
Scheme 4: Synthesis of imidazole derivative 10 initiated by an EDA complex.
Scheme 5: Synthesis of sulfamoylation product 12 initiated by an EDA complex.
Scheme 6: Mechanism of the synthesis of sulfamoylation product 12.
Scheme 7: Synthesis of indole derivative 22 initiated by an EDA complex.
Scheme 8: Synthesis of perfluoroalkylated pyrimidines 26 initiated by an EDA complex.
Scheme 9: Synthesis of phenanthridine derivative 29 initiated by an EDA complex.
Scheme 10: Synthesis of cis-tetrahydroquinoline derivative 32 initiated by an EDA complex.
Scheme 11: Mechanism of the synthesis of cis-tetrahydroquinoline derivative 32.
Scheme 12: Synthesis of phenanthridine derivative 38 initiated by an EDA complex.
Scheme 13: Synthesis of spiropyrroline derivative 40 initiated by an EDA complex.
Scheme 14: Synthesis of benzothiazole derivative 43 initiated by an EDA complex.
Scheme 15: Synthesis of perfluoroalkyl-s-triazine derivative 45 initiated by an EDA complex.
Scheme 16: Synthesis of indoline derivative 47 initiated by an EDA complex.
Scheme 17: Mechanism of the synthesis of spirocyclic indoline derivative 47.
Scheme 18: Synthesis of cyclobutane product 50 initiated by an EDA complex.
Scheme 19: Mechanism of the synthesis of spirocyclic indoline derivative 50.
Scheme 20: Synthesis of 1,3-oxazolidine compound 59 initiated by an EDA complex.
Scheme 21: Synthesis of trifluoromethylated product 61 initiated by an EDA complex.
Scheme 22: Synthesis of indole alkylation product 64 initiated by an EDA complex.
Scheme 23: Synthesis of perfluoroalkylation product 67 initiated by an EDA complex.
Scheme 24: Synthesis of hydrotrifluoromethylated product 70 initiated by an EDA complex.
Scheme 25: Synthesis of β-trifluoromethylated alkyne product 71 initiated by an EDA complex.
Scheme 26: Mechanism of the synthesis of 2-phenylthiophene derivative 74.
Scheme 27: Synthesis of allylated product 80 initiated by an EDA complex.
Scheme 28: Synthesis of trifluoromethyl-substituted alkynyl product 84 initiated by an EDA complex.
Scheme 29: Synthesis of dearomatized fluoroalkylation product 86 initiated by an EDA complex.
Scheme 30: Mechanism of the synthesis of dearomatized fluoroalkylation product 86.
Scheme 31: Synthesis of C(sp3)–H allylation product 91 initiated by an EDA complex.
Scheme 32: Synthesis of perfluoroalkylation product 93 initiated by an EDA complex.
Scheme 33: Synthesis of spirocyclic indolene derivative 95 initiated by an EDA complex.
Scheme 34: Synthesis of perfluoroalkylation product 97 initiated by an EDA complex.
Scheme 35: Synthesis of alkylated indole derivative 100 initiated by an EDA complex.
Scheme 36: Mechanism of the synthesis of alkylated indole derivative 100.
Scheme 37: Synthesis of arylated oxidized indole derivative 108 initiated by an EDA complex.
Scheme 38: Synthesis of 4-ketoaldehyde derivative 111 initiated by an EDA complex.
Scheme 39: Mechanism of the synthesis of 4-ketoaldehyde derivative 111.
Scheme 40: Synthesis of perfluoroalkylated olefin 118 initiated by an EDA complex.
Scheme 41: Synthesis of alkylation product 121 initiated by an EDA complex.
Scheme 42: Synthesis of acylation product 123 initiated by an EDA complex.
Scheme 43: Mechanism of the synthesis of acylation product 123.
Scheme 44: Synthesis of trifluoromethylation product 126 initiated by an EDA complex.
Scheme 45: Synthesis of unnatural α-amino acid 129 initiated by an EDA complex.
Scheme 46: Synthesis of thioether derivative 132 initiated by an EDA complex.
Scheme 47: Synthesis of S-aryl dithiocarbamate product 135 initiated by an EDA complex.
Scheme 48: Mechanism of the synthesis of S-aryl dithiocarbamate product 135.
Scheme 49: Synthesis of thioether product 141 initiated by an EDA complex.
Scheme 50: Mechanism of the synthesis of borate product 144.
Scheme 51: Synthesis of boronation product 148 initiated by an EDA complex.
Scheme 52: Synthesis of boration product 151 initiated by an EDA complex.
Scheme 53: Synthesis of boronic acid ester derivative 154 initiated by an EDA complex.
Scheme 54: Synthesis of β-azide product 157 initiated by an EDA complex.
Scheme 55: Decarboxylation reaction initiated by an EDA complex.
Scheme 56: Synthesis of amidated product 162 initiated by an EDA complex.
Scheme 57: Synthesis of diethyl phenylphosphonate 165 initiated by an EDA complex.
Scheme 58: Mechanism of the synthesis of diethyl phenylphosphonate derivative 165.
Scheme 59: Synthesis of (Z)-2-iodovinyl phenyl ether 168 initiated by an EDA complex.
Scheme 60: Mechanism of the synthesis of (Z)-2-iodovinyl phenyl ether derivative 168.
Scheme 61: Dehalogenation reaction initiated by an EDA complex.
Synthesis of tetrafluorinated piperidines from nitrones via a visible-light-promoted annelation reaction
- Vyacheslav I. Supranovich,
- Igor A. Dmitriev and
- Alexander D. Dilman
Beilstein J. Org. Chem. 2020, 16, 3104–3108, doi:10.3762/bjoc.16.260
- (CF2CF2) has advanced considerably over the last decade [20], and the use of preformed tetrafluorinated building blocks [21] provides the most efficient way of making these molecules. Recently, we disclosed a photoredox method for the reductive radical fluoroalkylation of nitrones [22][23][24]. We have
- iodine by treatment with zinc, followed by the reaction with iodine monochloride. The iodide 2b reacted quite rapidly with the nitrone but the expected fluoroalkylation product was not observed. Instead, the tetrafluorinated piperidine 3a was obtained in a moderate yield (Table 1, entry 2). Apparently
- , after the fluoroalkylation event, the reduction of the N–O bond had occurred. The corresponding addition of an additional amount of the reductant and performing the reaction in DMF led to product 3a in 84% isolated yield (Table 1, entry 4). Under the optimized conditions, a series of nitrones were
Graphical Abstract
Scheme 1: The construction of tetrafluorinated piperidines from nitrones.
Scheme 2: The scope of the annelation reaction for the synthesis of piperidines. Isolated yields are shown. a...
Scheme 3: The proposed mechanism of the photoredox annelation reaction (asc = ascorbic acid).
Photoredox-catalyzed silyldifluoromethylation of silyl enol ethers
- Vyacheslav I. Supranovich,
- Vitalij V. Levin and
- Alexander D. Dilman
Beilstein J. Org. Chem. 2020, 16, 1550–1553, doi:10.3762/bjoc.16.126
- Vyacheslav I. Supranovich Vitalij V. Levin Alexander D. Dilman N. D. Zelinsky Institute of Organic Chemistry, Leninsky prosp. 47, 119991 Moscow, Russian Federation 10.3762/bjoc.16.126 Abstract A method for the light-mediated fluoroalkylation of silyl enol ethers with (bromodifluoromethyl
- basic conditions required to activate inert C–Si bonds with the generation of carbanionic species. On the other hand, radical reactions offer different synthetic opportunities originating from the neutral character of the intermediates [6][7] and, accordingly, radical fluoroalkylation processes have
- source of hydrogen [21]. We thought that silane 1 could couple with silyl enol ethers in the presence of a photocatalyst affording fluoroalkylation products. Indeed, silyl enol ethers were found to be good acceptors of fluorinated radicals, and the resultant silyloxy-substituted radicals underwent single
Graphical Abstract
Scheme 1: Reactions of (bromodifluoromethyl)trimethylsilane (1).
Scheme 2: Optimization studies. Yield determined by 19F NMR spectroscopy using an internal standard.
Figure 1: Reaction of silyl enol ethers. Yields refer to isolated yields. aReaction time 24 h; b1.0 equiv of ...
Scheme 3: Proposed mechanism of the fluoroalkylation reaction.
Copper-based fluorinated reagents for the synthesis of CF2R-containing molecules (R ≠ F)
- Louise Ruyet and
- Tatiana Besset
Beilstein J. Org. Chem. 2020, 16, 1051–1065, doi:10.3762/bjoc.16.92
- vinyl bromides and iodides were efficiently achieved in high yields under mild reaction conditions. Noteworthy, the transformation turned out to be functional group tolerant and highly chemo- and stereroselective (Scheme 20). The group of Hu studied the fluoroalkylation of aryl halides. Indeed, a copper
- iodoalkenes. Only examples of isolated compounds were depicted. Fluoroalkylation of aryl halides via a RCF2CF2Cu species. Synthesis of perfluoroorganolithium copper species or perfluroalkylcopper derivatives from iodoperfluoroalkanes. Formation of the PhenCuCF2CF3 reagent by means of TFE and
Graphical Abstract
Scheme 1: Synthesis of the first isolable (NHC)CuCF2H complexes from TMSCF2H and their application for the sy...
Scheme 2: Pioneer works for the in situ generation of CuCF2H from TMSCF2H and from n-Bu3SnCF2H. Phen = 1,10-p...
Scheme 3: A Sandmeyer-type difluoromethylation reaction via the in situ generation of CuCF2H from TMSCF2H. a ...
Scheme 4: A one pot, two-step sequence for the difluoromethylthiolation of various classes of compounds via t...
Scheme 5: A copper-mediated oxidative difluoromethylation of terminal alkynes via the in situ generation of a...
Scheme 6: A copper-mediated oxidative difluoromethylation of heteroarenes.
Scheme 7: Synthesis of difluoromethylphosphonate-containing molecules using the in situ-generated CuCF2PO(OEt)...
Scheme 8: Synthesis of difluoromethylphosphonate-containing molecules using in situ-generated CuCF2PO(OEt)2 s...
Scheme 9: Synthesis of difluoromethylphosphonate-containing molecules using in situ-generated CuCF2PO(OEt)2 s...
Scheme 10: Synthesis of (diethylphosphono)difluoromethylthiolated molecules using in situ-generated CuCF2PO(OE...
Scheme 11: Access to (diethylphosphono)difluoromethylthiolated molecules via the in situ generation of CuCF2PO...
Scheme 12: Synthesis of (phenylsulfonyl)difluoromethyl-containing molecules via the in situ generation of CuCF2...
Scheme 13: Copper-mediated 1,1-difluoroethylation of diaryliodonium salts by using the in situ-generated CuCF2...
Scheme 14: Pioneer works for the pentafluoroethylation and heptafluoropropylation using a copper-based reagent...
Scheme 15: Pentafluoroethylation of (hetero)aryl bromides using the (Phen)CuCF2CF3 complex. 19F NMR yields wer...
Scheme 16: Synthesis of pentafluoroethyl ketones using the (Ph3P)Cu(phen)CF2CF3 reagent. 19F NMR yields were g...
Scheme 17: Synthesis of (Phen)2Cu(O2CCF2RF) and functionalization of (hetero)aryl iodides.
Scheme 18: Pentafluoroethylation of arylboronic acids and (hetero)aryl bromides via the in situ-generated CuCF2...
Scheme 19: In situ generation of CuCF2CF3 species from a cyclic-protected hexafluoroacetone and KCu(Ot-Bu)2. 19...
Scheme 20: Pentafluoroethylation of bromo- and iodoalkenes. Only examples of isolated compounds were depicted.
Scheme 21: Fluoroalkylation of aryl halides via a RCF2CF2Cu species.
Scheme 22: Synthesis of perfluoroorganolithium copper species or perfluroalkylcopper derivatives from iodoperf...
Scheme 23: Formation of the PhenCuCF2CF3 reagent by means of TFE and pentafluoroethylation of iodoarenes and a...
Scheme 24: Generation of a CuCF2CF3 reagent from TMSCF3 and applications.
Recent developments in photoredox-catalyzed remote ortho and para C–H bond functionalizations
- Rafia Siddiqui and
- Rashid Ali
Beilstein J. Org. Chem. 2020, 16, 248–280, doi:10.3762/bjoc.16.26
- selectivity, sustainability, and environmentally friendly bond constructions. C–H fluoroalkylation of arenes Fluoroalkylations in earlier reported methods required prefunctionalization of arenes, directing groups, etc. [175][176][177][178][179]. In this context, researchers were trying to find alternatives to
Graphical Abstract
Figure 1: List of photoredox catalysts used for C–H bond functionalizations.
Figure 2: List of metal-based photoredox catalysts used in this review article.
Figure 3: Jablonski diagram.
Figure 4: Photoredox catalysis via reductive or oxidative pathways. D = donor, A = acceptor, S = substrate, P...
Figure 5: Schematic representation of the combination of photoredox catalysis and transition metal catalysis.
Scheme 1: Weinreb amide C–H olefination.
Figure 6: Mechanism for the formation of 21 from 19 using photoredox catalyst 11.
Scheme 2: C–H olefination of phenolic ethers.
Scheme 3: Decarboxylative acylation of acetanilides.
Figure 7: Mechanism for the formation of 30 from acetanilide derivatives.
Scheme 4: Synthesis of fluorenone derivatives by intramolecular deoxygenative acylation of biaryl carboxylic ...
Figure 8: Mechanism for the photoredox-catalyzed synthesis of fluorenone derivatives.
Scheme 5: Synthesis of benzothiazoles via aerobic C–H thiolation.
Figure 9: Plausible mechanism for the construction of benzothiazoles from benzothioamides.
Scheme 6: Synthesis of benzothiazoles via oxidant-free C–H thiolation.
Figure 10: Mechanism involved in the synthesis of benzothiazoles via oxidant-free C–H thiolation.
Scheme 7: Synthesis of indoles via C–H cyclization of anilides with alkynes.
Scheme 8: Preparation of 3-trifluoromethylcoumarins via C–H cyclization of arylpropiolate esters.
Figure 11: Mechanistic pathway for the synthesis of coumarin derivatives via C–H cyclization.
Scheme 9: Monobenzoyloxylation without chelation assistance.
Figure 12: Plausible mechanism for the formation of 71 from 70.
Scheme 10: Aryl-substituted arenes prepared by inorganic photoredox catalysis using 12a.
Figure 13: Proposed mechanism for C–H arylations in the presence of 12a and a Pd catalyst.
Scheme 11: Arylation of purines via dual photoredox catalysis.
Scheme 12: Arylation of substituted arenes with an organic photoredox catalyst.
Scheme 13: C–H trifluoromethylation.
Figure 14: Proposed mechanism for the trifluoromethylation of 88.
Scheme 14: Synthesis of benzo-3,4-coumarin derivatives.
Figure 15: Plausible mechanism for the synthesis of substituted coumarins.
Scheme 15: Oxidant-free oxidative phosphonylation.
Figure 16: Mechanism proposed for the phosphonylation reaction of 100.
Scheme 16: Nitration of anilines.
Figure 17: Plausible mechanism for the nitration of aniline derivatives via photoredox catalysis.
Scheme 17: Synthesis of carbazoles via intramolecular amination.
Figure 18: Proposed mechanism for the formation of carbazoles from biaryl derivatives.
Scheme 18: Synthesis of substituted phenols using QuCN.
Figure 19: Mechanism for the synthesis of phenol derivatives with photoredox catalyst 8.
Scheme 19: Synthesis of substituted phenols with DDQ (5).
Figure 20: Possible mechanism for the generation of phenols with the aid of photoredox catalyst 5.
Scheme 20: Aerobic bromination of arenes using an acridinium-based photocatalyst.
Scheme 21: Aerobic bromination of arenes with anthraquinone.
Figure 21: Proposed mechanism for the synthesis of monobrominated compounds.
Scheme 22: Chlorination of benzene derivatives with Mes-Acr-MeClO4 (2).
Figure 22: Mechanism for the synthesis of 131 from 132.
Scheme 23: Chlorination of arenes with 4CzIPN (5a).
Figure 23: Plausible mechanism for the oxidative photocatalytic monochlorination using 5a.
Scheme 24: Monofluorination using QuCN-ClO4 (8).
Scheme 25: Fluorination with fluorine-18.
Scheme 26: Aerobic amination with acridinium catalyst 3a.
Figure 24: Plausible mechanism for the aerobic amination using acridinium catalyst 3a.
Scheme 27: Aerobic aminations with semiconductor photoredox catalyst 18.
Scheme 28: Perfluoroalkylation of arenes.
Scheme 29: Synthesis of benzonitriles in the presence of 3a.
Figure 25: Plausible mechanism for the synthesis of substituted benzonitrile derivatives in the presence of 3a....
Recent advances in transition-metal-catalyzed incorporation of fluorine-containing groups
- Xiaowei Li,
- Xiaolin Shi,
- Xiangqian Li and
- Dayong Shi
Beilstein J. Org. Chem. 2019, 15, 2213–2270, doi:10.3762/bjoc.15.218
- , agricultural, and materials industries. The incorporation of fluorine-containing groups into organic molecules can improve their chemical and physical properties, which attracts continuous interest in organic synthesis. Among various reported methods, transition-metal-catalyzed fluorination/fluoroalkylation
- . Keywords: catalysis; C-RF bond; fluorination; fluoroalkylation; transition metals; Introduction Compared with other halogens (Cl, Br, I), fluorine (F) has completely different physical and chemical properties, such as a unique electronic structure, strongest electronegativity, and small atomic radius
- -catalyzed fluorination/fluoroalkylation reactions represent an important and hot topic in fluorine chemistry. In addition, among the various metals developed, palladium is the most commonly employed transition metal, followed by copper owing to its high efficiency and cheapness. Meanwhile, other transition
Graphical Abstract
Scheme 1: The main three strategies of fluorination: nucleophilic, electrophilic and radical fluorination.
Scheme 2: Doyle’s Pd-catalyzed fluorination of allylic chlorides.
Scheme 3: Allylic fluorination of 2- and 3-substituted propenyl esters.
Scheme 4: Regioselective allylic fluorination of cinnamyl phosphorothioate esters.
Scheme 5: Palladium-catalyzed aliphatic C–H fluorination reported by Doyle.
Scheme 6: Pd-catalyzed enantioselective fluorination of α-ketoesters followed by stereoselective reduction to...
Scheme 7: Pd-catalyzed C(sp3)–H fluorination of oxindoles.
Scheme 8: C–H fluorination of 8-methylquinoline derivatives with F− reagents.
Scheme 9: Fluorination of α-cyano acetates reported by van Leeuwen.
Scheme 10: The catalytic enantioselective electrophilic C–H fluorination of α-chloro-β-keto phosphonates.
Scheme 11: Fluorination of unactivated C(sp3)–H bonds directed by the bidentate PIP auxiliary.
Scheme 12: Fluorination of C(sp3)–H bonds at the β-position of carboxylic acids.
Scheme 13: Enantioselective benzylic C–H fluorination with a chiral transient directing group.
Scheme 14: Microwave-heated Pd-catalyzed fluorination of aryl alcohols.
Scheme 15: Fluorination of aryl potassium trifluoroborates.
Scheme 16: C(sp2)–F bond formation using precatalyst [L·Pd]2(cod).
Scheme 17: Pd-catalyzed fluorination of (hetero)aryl triflates and bromides.
Scheme 18: The Pd-catalyzed C–H fluorination of arenes with Selectfluor/NFSI.
Scheme 19: Pd(II)-catalyzed ortho-monofluorination protocol for benzoic acids.
Scheme 20: Pd-catalyzed C(sp2)–H bond fluorination of 2-arylbenzothiazoles.
Scheme 21: Nitrate-promoted fluorination of aromatic and olefinic C(sp2)–H bonds and proposed mechanism.
Scheme 22: Fluorination of oxalyl amide-protected benzylamine derivatives.
Scheme 23: C–H fluorination of benzaldehydes with orthanilic acids as transient directing group.
Scheme 24: Pd(II)-catalyzed aryl C–H fluorination with various directing groups.
Scheme 25: Cu-catalyzed aliphatic, allylic, and benzylic fluorination.
Scheme 26: Cu-catalyzed SN2 fluorination of primary and secondary alkyl bromides.
Scheme 27: Copper-catalyzed fluorination of alkyl triflates.
Scheme 28: Cu-catalyzed fluorination of allylic bromides and chlorides.
Scheme 29: Synthetic strategy for the fluorination of active methylene compounds.
Scheme 30: Fluorination of β-ketoesters using a tartrate-derived bidentate bisoxazoline-Cu(II) complex.
Scheme 31: Highly enantioselective fluorination of β-ketoesters and N-Boc-oxindoles.
Scheme 32: Amide group-assisted site-selective fluorination of α-bromocarbonyl compounds.
Scheme 33: Cu-mediated aryl fluorination reported by Sanford [77].
Scheme 34: Mono- or difluorination reactions of benzoic acid derivatives.
Scheme 35: Cu-catalyzed fluorination of diaryliodonium salts with KF.
Scheme 36: Copper(I)-catalyzed cross-coupling of 2-pyridylaryl bromides.
Scheme 37: AgNO3-catalyzed decarboxylative fluorination of aliphatic carboxylic acids.
Scheme 38: The Mn-catalyzed aliphatic and benzylic C–H fluorination.
Scheme 39: Iron(II)-promoted C–H fluorination of benzylic substrates.
Scheme 40: Ag-catalyzed fluorodecarboxylation of carboxylic acids.
Scheme 41: Vanadium-catalyzed C(sp3)–H fluorination.
Scheme 42: AgNO3-catalyzed radical deboronofluorination of alkylboronates and boronic acids.
Scheme 43: Selective heterobenzylic C–H fluorination with Selectfluor reported by Van Humbeck.
Scheme 44: Fe(II)-catalyzed site-selective fluorination guided by an alkoxyl radical.
Scheme 45: Fluorination of allylic trichloroacetimidates reported by Nguyen et al.
Scheme 46: Iridium-catalyzed fluorination of allylic carbonates with TBAF(t-BuOH)4.
Scheme 47: Iridium-catalyzed asymmetric fluorination of allylic trichloroacetimidates.
Scheme 48: Cobalt-catalyzed α-fluorination of β-ketoesters.
Scheme 49: Nickel-catalyzed α-fluorination of various α-chloro-β-ketoesters.
Scheme 50: Ni(II)-catalyzed enantioselective fluorination of oxindoles and β-ketoesters.
Scheme 51: Scandium(III)-catalyzed asymmetric C–H fluorination of unprotected 3-substituted oxindoles.
Scheme 52: Iron-catalyzed directed C–H fluorination.
Scheme 53: Electrophilic silver-catalyzed Ar–F bond-forming reaction from arylstannanes.
Figure 1: Nucleophilic, electrophilic and radical CF3 sources.
Scheme 54: Cu(I)-catalyzed allylic trifluoromethylation of unactivated terminal olefins.
Scheme 55: Direct copper-catalyzed trifluoromethylation of allylsilanes.
Scheme 56: Cupper-catalyzed enantioselective trifluoromethylation of five and six-membered ring β-ketoesters.
Scheme 57: Cu-catalyzed highly stereoselective trifluoromethylation of secondary propargyl sulfonates.
Scheme 58: Remote C(sp3)–H trifluoromethylation of carboxamides and sulfonamides.
Scheme 59: Trifluoromethylation of allylsilanes with photoredox catalysis.
Scheme 60: Ag-catalyzed decarboxylative trifluoromethylation of aliphatic carboxylic acids in aqueous CH3CN.
Scheme 61: Decarboxylative trifluoromethylation of aliphatic carboxylic acids via combined photoredox and copp...
Scheme 62: Palladium-catalyzed Ar–CF3 bond-forming reaction.
Scheme 63: Palladium-catalyzed trifluoromethylation of arenes with diverse heterocyclic directing groups.
Scheme 64: Pd-catalyzed trifluoromethylation of indoles as reported by Liu.
Scheme 65: Pd-catalyzed trifluoromethylation of vinyl triflates and vinyl nonaflates.
Scheme 66: Pd(II)-catalyzed ortho-trifluoromethylation of aromatic C–H bonds.
Scheme 67: Visible-light-induced Pd(OAc)2-catalyzed ortho-trifluoromethylation of acetanilides with CF3SO2Na.
Scheme 68: CuI-catalyzed trifluoromethylation of aryl- and alkenylboronic acids.
Scheme 69: Cu-catalyzed trifluoromethylation of aryl- and vinylboronic acids.
Scheme 70: Copper-catalyzed trifluoromethylation of α,β-unsaturated carboxylic acids.
Scheme 71: Formation of C(sp2)–CF3 bond catalyzed by copper(I) complex.
Scheme 72: Loh’s Cu(I)-catalyzed trifluoromethylation of enamides and electron-deficient alkenes.
Scheme 73: Copper and iron-catalyzed decarboxylative tri- and difluoromethylation.
Scheme 74: Cu-catalyzed trifluoromethylation of hydrazones developed by Bouyssi.
Scheme 75: Cu(I)-catalyzed trifluoromethylation of terminal alkenes.
Scheme 76: Cu/Ag-catalyzed decarboxylative trifluoromethylation of cinnamic acids.
Scheme 77: Copper-catalyzed direct alkenyl C–H trifluoromethylation.
Scheme 78: Copper(I/II)-catalyzed direct trifluoromethylation of styrene derivatives.
Scheme 79: Regioselective trifluoromethylation of pivalamido arenes and heteroarenes.
Scheme 80: Synthesis of trifluoromethylquinones in the presence of copper(I).
Scheme 81: Oxidative trifluoromethylation of imidazoheterocycles in ionic liquid/water.
Scheme 82: A mild and fast continuous-flow trifluoromethylation of coumarins using a CuI/CF3SO2Na/TBHP system.
Scheme 83: Copper-catalyzed oxidative trifluoromethylation of various 8-aminoquinolines.
Scheme 84: PA-directed copper-catalyzed trifluoromethylation of anilines.
Scheme 85: Trifluoromethylation of potassium vinyltrifluoroborates catalyzed by Fe(II).
Scheme 86: Alkenyl trifluoromethylation catalyzed by Ru(phen)3Cl2 as photocatalyst.
Scheme 87: Ru-catalyzed trifluoromethylation of alkenes by Akita’s group.
Scheme 88: Ir-catalyzed Cvinyl–CF3 bond formation of α,β-unsaturated carboxylic acids.
Scheme 89: Ag(I)-catalyzed denitrative trifluoromethylation of β-nitrostyrenes.
Scheme 90: Photocatalyzed direct trifluoromethylation of aryl and heteroaryl C–H bonds.
Scheme 91: Rhenium (MTO)-catalyzed direct trifluoromethylation of aromatic substrates.
Scheme 92: Trifluoromethylation of unprotected anilines under [Ir(ppy)3] catalyst.
Scheme 93: Oxidative trifluoromethylation of imidazopyridines and imidazoheterocycles.
Scheme 94: Ruthenium-catalyzed trifluoromethylation of (hetero)arenes with trifluoroacetic anhydride.
Scheme 95: Phosphovanadomolybdic acid-catalyzed direct C–H trifluoromethylation.
Scheme 96: Picolinamide-assisted ortho-trifluoromethylation of arylamines.
Scheme 97: A nickel-catalyzed C–H trifluoromethylation of free anilines.
Scheme 98: Cu-mediated trifluoromethylation of terminal alkynes reported by Qing.
Scheme 99: Huang’s C(sp)–H trifluoromethylation using Togni’s reagent.
Scheme 100: Cu-catalyzed methods for trifluoromethylation with Umemoto’s reagent.
Scheme 101: The synthesis of alkynyl-CF3 compounds in the presence of fac-[Ir(ppy)3] under visible-light irradi...
Scheme 102: Pd-catalyzed Heck reaction reported by Reutrakul.
Scheme 103: Difluoromethylation of enamides and ene-carbamates.
Scheme 104: Difluoromethylation of α,β-unsaturated carboxylic acids.
Scheme 105: Copper-catalyzed direct C(sp2)–H difluoroacetylation reported by Pannecoucke and co-workers.
Scheme 106: Difluoroalkylation of aldehyde-derived hydrazones with functionalized difluoromethyl bromides.
Scheme 107: Photoredox-catalyzed C–H difluoroalkylation of aldehyde-derived hydrazones.
Scheme 108: Synergistic ruthenium(II)-catalyzed C–H difluoromethylation reported by Ackermann.
Scheme 109: Visible-light photocatalytic decarboxylation of α,β-unsaturated carboxylic acids.
Scheme 110: Synthesis of difluorinated ketones via S-alkyl dithiocarbamates obtained from acyl chlorides and po...
Scheme 111: Synthesis of aryl and heteroaryl difluoromethylated phosphonates.
Scheme 112: Difluoroalkylation of secondary propargyl sulfonates using Cu as the catalyst.
Scheme 113: Ru(II)-mediated para-selective difluoromethylation of anilides and their derivatives.
Scheme 114: Bulky diamine ligand promoted cross-coupling of difluoroalkyl bromides.
Scheme 115: Copper-catalyzed C3–H difluoroacetylation of quinoxalinones.
Scheme 116: Copper(I) chloride-catalyzed trifluoromethylthiolation of enamines, indoles and β-ketoesters.
Scheme 117: Copper-boxmi-catalyzed asymmetric trifluoromethylthiolation of β-ketoesters.
Scheme 118: Direct Cu-catalyzed trifluoromethylthiolation of boronic acids and alkynes.
Scheme 119: Cu-catalyzed synthesis of α-trifluoromethylthio-substituted ketones.
Scheme 120: Trifluoromethylthiolation reactions promoted by diazotriflone and copper.
Scheme 121: Halide activation of N-(trifluoromethylthio)phthalimide.
Scheme 122: The visible light-promoted trifluoromethylthiolation reported by Glorius.
Scheme 123: Synthesis of α-trifluoromethylthioesters via Goossen’s approach.
Scheme 124: Photoinduced trifluoromethylthiolation of diazonium salts.
Scheme 125: Ag-mediated trifluoromethoxylation of aryl stannanes and arylboronic acids.
Scheme 126: Catalytic (hetero)aryl C–H trifluoromethoxylation under visible light.
Scheme 127: Photoinduced C–H-bond trifluromethoxylation of (hetero)arenes.
Visible light-mediated difluoroalkylation of electron-deficient alkenes
- Vyacheslav I. Supranovich,
- Vitalij V. Levin,
- Marina I. Struchkova,
- Jinbo Hu and
- Alexander D. Dilman
Beilstein J. Org. Chem. 2018, 14, 1637–1641, doi:10.3762/bjoc.14.139
- attention in recent years [5][6][7][8]. Thus, besides the bioisosteric relationship with ethereal oxygen [9][10][11], the CF2-unit can influence the reactivity of adjacent functional groups [12][13] and can affect conformational properties of chain and cyclic molecules [14][15]. Radical fluoroalkylation of
- hydrogen and as a trigger for the generation of free radicals mediated by visible light. Difluoroalkylation of alkenes. Isolated yields are shown. a2 equiv of the alkene were used. Fluoroalkylation of alkenes. Proposed mechanism. Optimization studies. Supporting Information Supporting Information File 220
Graphical Abstract
Scheme 1: Fluoroalkylation of alkenes.
Figure 1: Difluoroalkylation of alkenes. Isolated yields are shown. a2 equiv of the alkene were used.
Scheme 2: Proposed mechanism.
Nucleophilic fluoroalkylation/cyclization route to fluorinated phthalides
- Masanori Inaba,
- Tatsuya Sakai,
- Shun Shinada,
- Tsuyuka Sugiishi,
- Yuta Nishina,
- Norio Shibata and
- Hideki Amii
Beilstein J. Org. Chem. 2018, 14, 182–186, doi:10.3762/bjoc.14.12
- considerable importance in chemistry [26][27][28][29][30][31][32]. Enantioselective fluoroalkylation/lactonization reactions are worth investigating since a new stereogenic carbon center next to the fluoroalkyl groups is generated in products 1. To the best of our knowledge, only one successful example of an
- fluoroalkylation should be solved in the future. Further examples for the promising utilization of fluorinated phthalides as building blocks can be found in [37]. Phthalide and fluorinated phthalides (1). Plausible reaction mechanism for the formation of phthalide 1a. Synthesis of fluorinated phthalides 1
Graphical Abstract
Scheme 1: Phthalide and fluorinated phthalides (1).
Scheme 2: Plausible reaction mechanism for the formation of phthalide 1a.
Scheme 3: Synthesis of fluorinated phthalides 1.
Scheme 4: Asymmetric synthesis of 1a using a chiral auxiliary.
Scheme 5: Catalytic asymmetric synthesis of 1a.
Regioselective decarboxylative addition of malonic acid and its mono(thio)esters to 4-trifluoromethylpyrimidin-2(1H)-ones
- Sergii V. Melnykov,
- Andrii S. Pataman,
- Yurii V. Dmytriv,
- Svitlana V. Shishkina,
- Mykhailo V. Vovk and
- Volodymyr A. Sukach
Beilstein J. Org. Chem. 2017, 13, 2617–2625, doi:10.3762/bjoc.13.259
- modern drug discovery and development area [9][10]. As a result of intensive research efforts over the last decades, efficient fluorination and fluoroalkylation methods have emerged to prepare previously challenging molecules decorated with fluorine atoms or fluorinated groups which make them practically
Graphical Abstract
Figure 1: Summary of the present study.
Scheme 1: Hydrogenation of compounds 4–6 and preparation of N1(3)-unsubstituted compounds 9–11d.
Figure 2: Molecular structure of compound 11b. Two enantiomers form a heterochiral dimer in the crystal state...
Palladium-catalyzed Heck-type reaction of secondary trifluoromethylated alkyl bromides
- Tao Fan,
- Wei-Dong Meng and
- Xingang Zhang
Beilstein J. Org. Chem. 2017, 13, 2610–2616, doi:10.3762/bjoc.13.258
- past decade, investigations mainly focused on direct fluorination or fluoroalkylation of aromatics [1][2][3][4][5]. Fluoroalkylated alkenes are a kind of important fluorinated structural motifs and have wide applications in medicinal chemistry and advanced functional materials [6][7][8][9]. However
Graphical Abstract
Scheme 1: Palladium-catalyzed Heck-type reaction of 2-bromo-1,1,1-trifluorohexane (2a) with alkenes 1. Reacti...
Scheme 2: Palladium-catalyzed Heck-type reaction of fluorinated secondary bromides (iodides) 2 with alkenes 1...
Scheme 3: Radical clock experiment for mechanistic studies.
Scheme 4: Proposed mechanism.
Comparative profiling of well-defined copper reagents and precursors for the trifluoromethylation of aryl iodides
- Peter T. Kaplan,
- Jessica A. Lloyd,
- Mason T. Chin and
- David A. Vicic
Beilstein J. Org. Chem. 2017, 13, 2297–2303, doi:10.3762/bjoc.13.225
- employed directly or generated in situ from precursors by published reports. Relative reactivities were also found to highly dependent on the nature of the iodoarenes. Keywords: benchmarking; copper; fluorine; fluoroalkylation; trifluoromethylation; Introduction Selectively fluorinated molecules that
Graphical Abstract
Scheme 1: Reagents and precursors used for trifluoromethylation reactions.
Scheme 2: Preparation of [(SIMes)2Cu][Cu(CF3)2].
Scheme 3: General protocol for reactions described in Figure 1.
Figure 1: Yields of 4-(trifluoromethyl)-1,1’-biphenyl over time for the systems described in Scheme 1. These runs rep...
Figure 2: Yields of 4-(trifluoromethyl)-1,1’-biphenyl over time for the systems described in Scheme 1. Conditions for ...
Figure 3: Reaction of 1-iodo-4-methylbenzene with systems A1, A2, and B2 to produce 1-methyl-4-(trifluorometh...
Figure 4: Reaction of 2-iodotoluene with systems A1, A2, and B2 to produce 1-methyl-2-(trifluoromethyl)benzen...
Rearrangements of organic peroxides and related processes
- Ivan A. Yaremenko,
- Vera A. Vil’,
- Dmitry V. Demchuk and
- Alexander O. Terent’ev
Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162
Graphical Abstract
Figure 1: The named transformations considered in this review.
Scheme 1: The Baeyer–Villiger oxidation.
Scheme 2: The general mechanism of the peracid-promoted Baeyer–Villiger oxidation.
Scheme 3: General mechanism of the Lewis acid-catalyzed Baeyer–Villiger rearrangement.
Scheme 4: The theoretically studied mechanism of the BV oxidation reaction promoted by H2O2 and the Lewis aci...
Scheme 5: Proton movements in the transition states of the Baeyer–Villiger oxidation.
Scheme 6: The dependence of the course of the Baeyer–Villiger oxidation on the type of O–O-bond cleavage in t...
Scheme 7: The acid-catalyzed Baeyer–Villiger oxidation of cyclic epoxy ketones 22.
Scheme 8: Oxidation of isophorone oxide 29.
Scheme 9: Synthesis of acyl phosphate 32 from acyl phosphonate 31.
Scheme 10: Synthesis of aflatoxin B2 (36).
Scheme 11: The Baeyer–Villiger rearrangement of ketones 37 to lactones 38.
Scheme 12: Synthesis of 3,4-dimethoxybenzoic acid (40) via Baeyer–Villiger oxidation.
Scheme 13: Oxone transforms α,β-unsaturated ketones 43 into vinyl acetates 44.
Scheme 14: The Baeyer–Villiger oxidation of ketones 45 using diaryl diselenide and hydrogen peroxide.
Scheme 15: Baeyer–Villiger oxidation of (E)-2-methylenecyclobutanones.
Scheme 16: Oxidation of β-ionone (56) by H2O2/(BnSe)2 with formation of (E)-2-(2,6,6-trimethylcyclohex-1-en-1-...
Scheme 17: The mechanism of oxidation of ketones 58a–f by hydrogen peroxide in the presence of arsonated polys...
Scheme 18: Oxidation of ketone (58b) by H2O2 to 6-methylcaprolactone (59b) catalyzed by Pt complex 66·BF4.
Scheme 19: Oxidation of ketones 67 with H2O2 in the presence of [(dppb}Pt(µ-OH)]22+.
Scheme 20: The mechanism of oxidation of ketones 67 in the presence of [(dppb}Pt(µ-OH)]22+ and H2O2.
Scheme 21: Oxidation of benzaldehydes 69 in the presence of the H2O2/MeReO3 system.
Scheme 22: Oxidation of acetophenones 72 in the presence of the H2O2/MeReO3 system.
Scheme 23: Baeyer–Villiger oxidation of 2-adamantanone (45c) in the presence of Sn-containing mesoporous silic...
Scheme 24: Aerobic Baeyer–Villiger oxidation of ketones 76 using metal-free carbon.
Scheme 25: A regioselective Baeyer-Villiger oxidation of functionalized cyclohexenones 78 into a dihydrooxepin...
Scheme 26: The oxidation of aldehydes and ketones 80 by H2O2 catalyzed by Co4HP2Mo15V3O62.
Scheme 27: The cleavage of ketones 82 with hydrogen peroxide in alkaline solution.
Scheme 28: Oxidation of ketones 85 to esters 86 with H2O2–urea in the presence of KHCO3.
Scheme 29: Mechanism of the asymmetric oxidation of cyclopentane-1,2-dione 87a with the Ti(OiPr)4/(+)DET/t-BuO...
Scheme 30: The oxidation of cis-4-tert-butyl-2-fluorocyclohexanone (93) with m-chloroperbenzoic acid.
Scheme 31: The mechanism of the asymmetric oxidation of 3-substituted cyclobutanone 96a in the presence of chi...
Scheme 32: Enantioselective Baeyer–Villiger oxidation of cyclic ketones 98.
Scheme 33: Regio- and enantioselective Baeyer–Villiger oxidation of cyclic ketones 101.
Scheme 34: The proposed mechanism of the Baeyer–Villiger oxidation of acetal 105f.
Scheme 35: Synthesis of hydroxy-10H-acridin-9-one 117 from tetramethoxyanthracene 114.
Scheme 36: The Baeyer–Villiger oxidation of the fully substituted pyrrole 120.
Scheme 37: The Criegee rearrangement.
Scheme 38: The mechanism of the Criegee reaction of a peracid with a tertiary alcohol 122.
Scheme 39: Criegee rearrangement of decaline ethylperoxoate 127 into ketal 128.
Scheme 40: The ionic cleavage of 2-methoxy-2-propyl perester 129.
Scheme 41: The Criegee rearrangement of α-methoxy hydroperoxide 136.
Scheme 42: Synthesis of enol esters and acetals via the Criegee rearrangement.
Scheme 43: Proposed mechanism of the transformation of 1-hydroperoxy-2-oxabicycloalkanones 147a–d.
Scheme 44: Transformation of 3-hydroxy-1,2-dioxolanes 151 into diketone derivatives 152.
Scheme 45: Criegee rearrangement of peroxide 153 with the mono-, di-, and tri-O-insertion.
Scheme 46: The sequential Criegee rearrangements of adamantanes 157a,b.
Scheme 47: Synthesis of diaryl carbonates 160a–d from triarylmethanols 159a–d through successive oxygen insert...
Scheme 48: The synthesis of sesquiterpenes 162 from ketone 161 with a Criegee rearrangement as one key step.
Scheme 49: Synthesis of trans-hydrindan derivatives 164, 165.
Scheme 50: The Hock rearrangement.
Scheme 51: The general scheme of the cumene process.
Scheme 52: The Hock rearrangement of aliphatic hydroperoxides.
Scheme 53: The mechanism of solvolysis of brosylates 174a–c and spiro cyclopropyl carbinols 175a–c in THF/H2O2....
Scheme 54: The fragmentation mechanism of hydroperoxy acetals 178 to esters 179.
Scheme 55: The acid-catalyzed rearrangement of phenylcyclopentyl hydroperoxide 181.
Scheme 56: The peroxidation of tertiary alcohols in the presence of a catalytic amount of acid.
Scheme 57: The acid-catalyzed reaction of bicyclic secondary alcohols 192 with hydrogen peroxide.
Scheme 58: The photooxidation of 5,6-disubstituted 3,4-dihydro-2H-pyrans 196.
Scheme 59: The oxidation of tertiary alcohols 200a–g, 203a,b, and 206.
Scheme 60: Transformation of functional peroxide 209 leading to 2,3-disubstitued furans 210 in one step.
Scheme 61: The synthesis of carbazoles 213 via peroxide rearrangement.
Scheme 62: The construction of C–N bonds using the Hock rearrangement.
Scheme 63: The synthesis of moiety 218 from 217 which is a structural motif in the antitumor–antibiotic of CC-...
Scheme 64: The in vivo oxidation steps of cholesterol (219) by singlet oxygen.
Scheme 65: The proposed mechanism of the rearrangement of cholesterol-5α-OOH 220.
Scheme 66: Photochemical route to artemisinin via Hock rearrangement of 223.
Scheme 67: The Kornblum–DeLaMare rearrangement.
Scheme 68: Kornblum–DeLaMare transformation of 1-phenylethyl tert-butyl peroxide (225).
Scheme 69: The synthesis 4-hydroxyenones 230 from peroxide 229.
Scheme 70: The Kornblum–DeLaMare rearrangement of peroxide 232.
Scheme 71: The reduction of peroxide 234.
Scheme 72: The Kornblum–DeLaMare rearrangement of endoperoxide 236.
Scheme 73: The rearrangement of peroxide 238 under Kornblum–DeLaMare conditions.
Scheme 74: The proposed mechanism of rearrangement of peroxide 238.
Scheme 75: The Kornblum–DeLaMare rearrangement of peroxides 242a,b.
Scheme 76: The base-catalyzed rearrangements of bicyclic endoperoxides having electron-withdrawing substituent...
Scheme 77: The base-catalyzed rearrangements of bicyclic endoperoxides 249a,b having electron-donating substit...
Scheme 78: The base-catalyzed rearrangements of bridge-head substituted bicyclic endoperoxides 251a,b.
Scheme 79: The Kornblum–DeLaMare rearrangement of hydroperoxide 253.
Scheme 80: Synthesis of β-hydroxy hydroperoxide 254 from endoperoxide 253.
Scheme 81: The amine-catalyzed rearrangement of bicyclic endoperoxide 263.
Scheme 82: The base-catalyzed rearrangement of meso-endoperoxide 268 into 269.
Scheme 83: The photooxidation of 271 and subsequent Kornblum–DeLaMare reaction.
Scheme 84: The Kornblum–DeLaMare rearrangement as one step in the oxidation reaction of enamines.
Scheme 85: The Kornblum–DeLaMare rearrangement of 3,5-dihydro-1,2-dioxenes 284, 1,2-dioxanes 286, and tert-but...
Scheme 86: The Kornblum–DeLaMare rearrangement of epoxy dioxanes 290a–d.
Scheme 87: Rearrangement of prostaglandin H2 292.
Scheme 88: The synthesis of epicoccin G (297).
Scheme 89: The Kornblum–DeLaMare rearrangement used in the synthesis of phomactin A.
Scheme 90: The Kornblum–DeLaMare rearrangement in the synthesis of 3H-quinazolin-4-one 303.
Scheme 91: The Kornblum–DeLaMare rearrangement in the synthesis of dolabriferol (308).
Scheme 92: Sequential transformation of 3-substituted 2-pyridones 309 into 3-hydroxypyridine-2,6-diones 311 in...
Scheme 93: The Kornblum–DeLaMare rearrangement of peroxide 312 into hydroxy enone 313.
Scheme 94: The Kornblum–DeLaMare rearrangement in the synthesis of polyfunctionalized carbonyl compounds 317.
Scheme 95: The Kornblum–DeLaMare rearrangement in the synthesis of (Z)-β-perfluoroalkylenaminones 320.
Scheme 96: The Kornblum–DeLaMare rearrangement in the synthesis of γ-ketoester 322.
Scheme 97: The Kornblum–DeLaMare rearrangement in the synthesis of diterpenoids 326 and 328.
Scheme 98: The synthesis of natural products hainanolidol (331) and harringtonolide (332) from peroxide 329.
Scheme 99: The synthesis of trans-fused butyrolactones 339 and 340.
Scheme 100: The synthesis of leucosceptroid C (343) and leucosceptroid P (344) via the Kornblum–DeLaMare rearra...
Scheme 101: The Dakin oxidation of arylaldehydes or acetophenones.
Scheme 102: The mechanism of the Dakin oxidation.
Scheme 103: A solvent-free Dakin reaction of aromatic aldehydes 356.
Scheme 104: The organocatalytic Dakin oxidation of electron-rich arylaldehydes 358.
Scheme 105: The Dakin oxidation of electron-rich arylaldehydes 361.
Scheme 106: The Dakin oxidation of arylaldehydes 358 in water extract of banana (WEB).
Scheme 107: A one-pot approach towards indolo[2,1-b]quinazolines 364 from indole-3-carbaldehydes 363 through th...
Scheme 108: The synthesis of phenols 367a–c from benzaldehydes 366a-c via acid-catalyzed Dakin oxidation.
Scheme 109: Possible transformation paths of the highly polarized boric acid coordinated H2O2–aldehyde adduct 3...
Scheme 110: The Elbs oxidation of phenols 375 to hydroquinones.
Scheme 111: The mechanism of the Elbs persulfate oxidation of phenols 375 affording p-hydroquinones 376.
Scheme 112: Oxidation of 2-pyridones 380 under Elbs persulfate oxidation conditions.
Scheme 113: Synthesis of 3-hydroxy-4-pyridone (384) via an Elbs oxidation of 4-pyridone (382).
Scheme 114: The Schenck rearrangement.
Scheme 115: The Smith rearrangement.
Scheme 116: Three main pathways of the Schenck rearrangement.
Scheme 117: The isomerization of hydroperoxides 388 and 389.
Scheme 118: Trapping of dioxacyclopentyl radical 392 by oxygen.
Scheme 119: The hypothetical mechanism of the Schenck rearrangement of peroxide 394.
Scheme 120: The autoxidation of oleic acid (397) with the use of labeled isotope 18O2.
Scheme 121: The rearrangement of 18O-labeled hydroperoxide 400 under an atmosphere of 16O2.
Scheme 122: The rearrangement of the oleate-derived allylic hydroperoxides (S)-421 and (R)-425.
Scheme 123: Mechanisms of Schenck and Smith rearrangements.
Scheme 124: The rearrangement and cyclization of 433.
Scheme 125: The Wieland rearrangement.
Scheme 126: The rearrangement of bis(triphenylsilyl) 439 or bis(triphenylgermyl) 441 peroxides.
Scheme 127: The oxidative transformation of cyclic ketones.
Scheme 128: The hydroxylation of cyclohexene (447) in the presence of tungstic acid.
Scheme 129: The oxidation of cyclohexene (447) under the action of hydrogen peroxide.
Scheme 130: The reaction of butenylacetylacetone 455 with hydrogen peroxide.
Scheme 131: The oxidation of bridged 1,2,4,5-tetraoxanes.
Scheme 132: The proposed mechanism for the oxidation of bridged 1,2,4,5-tetraoxanes.
Scheme 133: The rearrangement of ozonides.
Scheme 134: The acid-catalyzed oxidative rearrangement of malondialdehydes 462 under the action of H2O2.
Scheme 135: Pathways of the Lewis acid-catalyzed cleavage of dialkyl peroxides 465 and ozonides 466.
Scheme 136: The mechanism of the transformation of (tert-butyldioxy)cyclohexanedienones 472.
Scheme 137: The synthesis of Vitamin K3 from 472a.
Scheme 138: Proposed mechanism for the transformation of 478d into silylated endoperoxide 479d.
Scheme 139: The rearrangement of hydroperoxide 485 to form diketone 486.
Scheme 140: The base-catalyzed rearrangement of cyclic peroxides 488a–g.
Scheme 141: Synthesis of chiral epoxides and aldols from peroxy hemiketals 491.
Scheme 142: The multistep transformation of (R)-carvone (494) to endoperoxides 496a–e.
Scheme 143: The decomposition of anthracene endoperoxide 499.
Scheme 144: Synthesis of esters 503 from aldehydes 501 via rearrangement of peroxides 502.
Scheme 145: Two possible paths for the base-promoted decomposition of α-azidoperoxides 502.
Scheme 146: The Story decomposition of cyclic diperoxide 506a.
Scheme 147: The Story decomposition of cyclic triperoxide 506b.
Scheme 148: The thermal rearrangement of endoperoxides A into diepoxides B.
Scheme 149: The transformation of peroxide 510 in the synthesis of stemolide (511).
Scheme 150: The possible mechanism of the rearrangement of endoperoxide 261g.
Scheme 151: The photooxidation of indene 517.
Scheme 152: The isomerization of ascaridole (523).
Scheme 153: The isomerization of peroxide 525.
Scheme 154: The thermal transformation of endoperoxide 355.
Scheme 155: The photooxidation of cyclopentadiene (529) at a temperature higher than 0 °C.
Scheme 156: The thermal rearrangement of endoperoxides 538a,b.
Scheme 157: The transformation of peroxides 541.
Scheme 158: The thermal rearrangements of strained cyclic peroxides.
Scheme 159: The thermal rearrangement of diacyl peroxide 551 in the synthesis of C4-epi-lomaiviticin B core 553....
Scheme 160: The 1O2 oxidation of tryptophan (554) and rearrangement of dioxetane intermediate 555.
Scheme 161: The Fe(II)-promoted cleavage of aryl-substituted bicyclic peroxides.
Scheme 162: The proposed mechanism of the Fe(II)-promoted rearrangement of 557a–c.
Scheme 163: The reaction of dioxolane 563 with Fe(II) sulfate.
Scheme 164: Fe(II)-promoted rearrangement of 1,2-dioxane 565.
Scheme 165: Fe(II) cysteinate-promoted rearrangement of 1,2-dioxolane 568.
Scheme 166: The transformation of 1,2-dioxanes 572a–c under the action of FeCl2.
Scheme 167: Fe(II) cysteinate-promoted transformation of tetraoxane 574.
Scheme 168: The CoTPP-catalyzed transformation of bicyclic endoperoxides 600a–d.
Scheme 169: The CoTPP-catalyzed transformation of epoxy-1,2-dioxanes.
Scheme 170: The Ru(II)-catalyzed reactions of 1,4-endoperoxide 261g.
Scheme 171: The Ru(II)-catalyzed transformation as a key step in the synthesis of elyiapyrone A (610) from 1,4-...
Scheme 172: Peroxides with antimalarial activity.
Scheme 173: The interaction of iron ions with artemisinin (616).
Scheme 174: The interaction of FeCl2 with 1,2-dioxanes 623, 624.
Scheme 175: The mechanism of reaction 623 and 624 with Fe(II)Cl2.
Scheme 176: The reaction of bicyclic natural endoperoxides G3-factors 631–633 with FeSO4.
Scheme 177: The transformation of terpene cardamom peroxide 639.
Scheme 178: The different ways of the cleavage of tetraoxane 643.
Scheme 179: The LC–MS analysis of interaction of tetraoxane 646 with iron(II)heme 647.
Scheme 180: The rearrangement of 3,6-epidioxy-1,10-bisaboladiene (EDBD, 649).
Scheme 181: Easily oxidized substrates.
Scheme 182: Biopathway of synthesis of prostaglandins.
Scheme 183: The reduction and rearrangements of isoprostanes.
Scheme 184: The partial mechanism for linoleate 658 oxidation.
Scheme 185: The transformation of lipid hydroperoxide.
Scheme 186: The acid-catalyzed cleavage of the product from free-radical oxidation of cholesterol (667).
Scheme 187: Two pathways of catechols oxidation.
Scheme 188: Criegee-like or Hock-like rearrangement of the intermediate hydroperoxide 675 in dioxygenase enzyme...
Scheme 189: Carotinoides 679 cleavage by carotenoid cleavage dioxygenases.
Carbon–carbon bond cleavage for Cu-mediated aromatic trifluoromethylations and pentafluoroethylations
- Tsuyuka Sugiishi,
- Hideki Amii,
- Kohsuke Aikawa and
- Koichi Mikami
Beilstein J. Org. Chem. 2015, 11, 2661–2670, doi:10.3762/bjoc.11.286
- -okayama, Meguro-ku, Tokyo 152-8552, Japan 10.3762/bjoc.11.286 Abstract This short review highlights the copper-mediated fluoroalkylation using perfluoroalkylated carboxylic acid derivatives. Carbon–carbon bond cleavage of perfluoroalkylated carboxylic acid derivatives takes place in fluoroalkylation
- reactions at high temperature (150–200 °C) or under basic conditions to generate fluoroalkyl anion sources for the formation of fluoroalkylcopper species. The fluoroalkylation reactions, which proceed through decarboxylation or tetrahedral intermediates, are useful protocols for the synthesis of
- , the research activity on selective fluorination and trifluoromethylation has reached a mature state. The progress in fluoroalkylation of organic compounds could be accelerated by the use of fluoroalkylating reagents, which are inexpensive and easy to handle. Perfluoroalkyl carboxylic acid derivatives
Graphical Abstract
Scheme 1: Trifluoromethylation using trifluoroacetate.
Scheme 2: Decarboxylative pentafluoroethylation and its application.
Scheme 3: Trifluoromethyation with trifluoroacetate in a flow system.
Scheme 4: Trifluoromethylation of 4-bromotoluene by [(NHC)Cu(TFA)].
Scheme 5: Trifluoromethylation of aryl iodides with small amounts of Cu and Ag2O. aThe yield was determined b...
Scheme 6: C–H trifluoromethylation of arenes using trifluoroacetic acid.
Scheme 7: CF3Cu generated from chlorofluoroacetate and CuI.
Scheme 8: [18F]Trifluoromethyation with difluorocarbenes for PET. aRadiochemical yield determined by HPLC.
Scheme 9: Trifluoromethylation with trifluoroacetate and copper iodide.
Scheme 10: Preparation of trifluoromethylcopper from trifluoromethyl ketone.
Scheme 11: Trifluoromethylation of aryl iodides. aIsolated yield. b1 equivalent each of CF3Cu reagent and 1,10...
Scheme 12: Pentafluoroethylation of aryl bromides. aYield was determined by 19F NMR analysis using benzotriflu...
Scheme 13: Perfluoroalkylation reactions of arylboronic acids. aIsolated yield. bDMF was used instead of tolue...
Scheme 14: Trifluoromethylation with silylated hemiaminal of fluoral.
Scheme 15: Catalytic trifluoromethylation with a fluoral derivative.
Scheme 16: The scope of Cu-catalyzed aromatic trifluoromethylation. The yield was determined by 19F NMR analys...
Scheme 17: Plausible mechanism of Cu-catalyzed aromatic trifluoromethylation [53].
Flow microreactor synthesis in organo-fluorine chemistry
- Hideki Amii,
- Aiichiro Nagaki and
- Jun-ichi Yoshida
Beilstein J. Org. Chem. 2013, 9, 2793–2802, doi:10.3762/bjoc.9.314
- by nucleophilic substitution reactions using [18F]-fluoride ion (Scheme 7) [55][56][57][58][59][60][61][62][63][64][65][66][67]. For not only fluorination/fluoroalkylation, but also for defluorination, flow microreactor synthesis is quite effective. Defluorination involving a nucleophilic addition
Graphical Abstract
Scheme 1: Direct fluorination using microreactor systems.
Scheme 2: Use of DAST in continuous-flow reactors.
Scheme 3: Flow microreactor synthesis of fluorinated epoxides.
Scheme 4: Highly controlled isomerization of gem-difluoroalkenes.
Scheme 5: Flow system for catalytic aromatic fluorination.
Scheme 6: Continuous-flow reactor for electrophilic aromatic fluorination.
Scheme 7: Examples of [18F]-radiolabeled molecular imaging probes.
Scheme 8: Flow microreactor synthesis of dipeptides.
Scheme 9: Flow synthesis involving SNAr reactions.
Scheme 10: Flow synthesis of fluoroquinolone antibiotics.
Scheme 11: Highly controlled formation of PFPMgBr.
Scheme 12: Selective flow synthesis of photochromic diarylethenes.
Scheme 13: Flow microreactor system for perfluoroalkylation by generation of perfluoroalkyllithiums in the pre...
Scheme 14: Integrated flow microreactor system for perfluoroalkylation by generation of perfluoroalkyllithiums...
Recent advances in transition metal-catalyzed Csp2-monofluoro-, difluoro-, perfluoromethylation and trifluoromethylthiolation
- Grégory Landelle,
- Armen Panossian,
- Sergiy Pazenok,
- Jean-Pierre Vors and
- Frédéric R. Leroux
Beilstein J. Org. Chem. 2013, 9, 2476–2536, doi:10.3762/bjoc.9.287
- monofluoromethylation was described by J. Hu. Aryl iodides were submitted to a Cu-catalyzed (CuTC = copper thiophene-2-carboxylate) debenzoylative fluoroalkylation with 2-PySO2CHFCOR followed by desulfonylation (Scheme 2) [49]. It has been shown that the (2-pyridyl)sulfonyl moiety is important for the Cu-catalysis. 2
- decarboxylative fluoroalkylation (Table 1) [61]. A wide range of α,β-unsaturated carboxylic acids afforded the corresponding difluoromethylated alkenes in high yields and with excellent E/Z selectivity. The putative mechanism for this copper-catalyzed decarboxylative fluoro-alkylation involves the iodine–oxygen
Graphical Abstract
Scheme 1: Pd-catalyzed monofluoromethylation of pinacol phenylboronate [44].
Scheme 2: Cu-catalyzed monofluoromethylation with 2-PySO2CHFCOR followed by desulfonylation [49].
Scheme 3: Cu-catalyzed difluoromethylation with α-silyldifluoroacetates [57].
Figure 1: Mechanism of the Cu-catalyzed C–CHF2 bond formation of α,β-unsaturated carboxylic acids through dec...
Scheme 4: Fe-catalyzed decarboxylative difluoromethylation of cinnamic acids [62].
Scheme 5: Preliminary experiments for investigation of the mechanism of the C–H trifluoromethylation of N-ary...
Figure 2: Plausible catalytic cycle proposed by Z.-J. Shi et al. for the trifluoromethylation of acetanilides ...
Figure 3: Plausible catalytic cycle proposed by M. S. Sanford et al. for the perfluoroalkylation of simple ar...
Figure 4: Postulated reaction pathway for the Ag/Cu-catalyzed trifluoromethylation of aryl iodides by Z. Q. W...
Figure 5: Postulated reaction mechanism for Cu-catalyzed trifluoromethylation reaction using MTFA as trifluor...
Scheme 6: Formal Heck-type trifluoromethylation of vinyl(het)arenes by M. Sodeoka et al. [83].
Figure 6: Proposed catalytic cycle for the copper-catalyzed trifluoromethylation of (het)arenes in presence o...
Figure 7: Proposed catalytic cycle for the copper-catalyzed trifluoromethylation of N,N-disubstituted (hetero...
Figure 8: Proposed catalytic cycle by Y. Zhang and J. Wang et al. for the copper-catalyzed trifluoromethylati...
Figure 9: Mechanistic rationale for the trifluoromethylation of arenes in presence of Langlois’s reagent and ...
Scheme 7: Trifluoromethylation of 4-acetylpyridine with Langlois’s reagent by P. S. Baran et al. (* Stirring ...
Scheme 8: Catalytic copper-facilitated perfluorobutylation of benzene with C4F9I and benzoyl peroxide [90].
Figure 10: F.-L. Qing et al.’s proposed mechanism for the copper-catalyzed trifluoromethylation of (hetero)are...
Figure 11: Mechanism of the Cu-catalyzed/Ru-photocatalyzed trifluoromethylation and perfluoroalkylation of ary...
Figure 12: Proposed mechanism for the Cu-catalyzed trifluoromethylation of aryl- and vinyl boronic acids with ...
Figure 13: Possible mechanism for the Cu-catalyzed decarboxylative trifluoromethylation of cinnamic acids [62].
Scheme 9: Ruthenium-catalyzed perfluoroalkylation of alkenes and (hetero)arenes with perfluoroalkylsulfonyl c...
Figure 14: N. Kamigata et al.’s proposed mechanism for the Ru-catalyzed perfluoroalkylation of alkenes and (he...
Figure 15: Proposed mechanism for the Ru-catalyzed photoredox trifluoromethylation of (hetero)arenes with trif...
Figure 16: Late-stage trifluoromethylation of pharmaceutically relevant molecules with trifluoromethanesulfony...
Figure 17: Proposed mechanism for the trifluoromethylation of alkenes with trifluoromethyl iodide under Ru-bas...
Scheme 10: Formal perfluoroakylation of terminal alkenes by Ru-catalyzed cross-metathesis with perfluoroalkyle...
Figure 18: One-pot Ir-catalyzed borylation/Cu-catalyzed trifluoromethylation of complex small molecules by Q. ...
Figure 19: Mechanistic proposal for the Ni-catalyzed perfluoroalkylation of arenes and heteroarenes with perfl...
Scheme 11: Electrochemical Ni-catalyzed perfluoroalkylation of 2-phenylpyridine (Y. H. Budnikova et al.) [71].
Scheme 12: Fe(II)-catalyzed trifluoromethylation of arenes and heteroarenes with trifluoromethyl iodide (T. Ya...
Figure 20: Mechanistic proposal by T. Yamakawa et al. for the Fe(II)-catalyzed trifluoromethylation of arenes ...
Scheme 13: Ytterbium-catalyzed perfluoroalkylation of dihydropyran with perfluoroalkyl iodide (Y. Ding et al.) ...
Figure 21: Mechanistic proposal by A. Togni et al. for the rhenium-catalyzed trifluoromethylation of arenes an...
Figure 22: Mechanism of the Cu-catalyzed oxidative trifluoromethylthiolation of arylboronic acids with TMSCF3 ...
Scheme 14: Removal of the 8-aminoquinoline auxiliary [136].
Figure 23: Mechanism of the Cu-catalyzed trifluoromethylthiolation of C–H bonds with a trifluoromethanesulfony...
Enantioselective nucleophilic difluoromethylation of aromatic aldehydes with Me3SiCF2SO2Ph and PhSO2CF2H reagents catalyzed by chiral quaternary ammonium salts
- Chuanfa Ni,
- Fang Wang and
- Jinbo Hu
Beilstein J. Org. Chem. 2008, 4, No. 21, doi:10.3762/bjoc.4.21
- agrochemicals and 20% of pharmaceuticals on the market contain fluorine [1][2]; as a result, fluorine is highlighted as the second most utilized hetero-element (after nitrogen) in life science-oriented research [3]. Nucleophilic fluoroalkylation, typically involving the transfer of a fluorinated carbanion (Rf
- played an important role in tuning the fluoroalkylation reactivity towards aldehydes and ketones, i.e. aldehydes showed higher reactivity than ketones [12]. In connection with our studies on selective fluoroalkylation reactions, herein we disclose the first example of catalytic enantioselective
Graphical Abstract
Scheme 1: Structure of chiral quaternary ammonium salts.
Scheme 2: Determination of the absolute configuration of (+)-3a.
