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Search for "phenols" in Full Text gives 189 result(s) in Beilstein Journal of Organic Chemistry.
Aromatic and heterocyclic perfluoroalkyl sulfides. Methods of preparation
- Vladimir N. Boiko
Beilstein J. Org. Chem. 2010, 6, 880–921, doi:10.3762/bjoc.6.88
- longer perfluoroalkyl sulfides because the required aryl perchloroalkyl sulfide precursors are not easily accessible [57][58]. However, pentafluoroethyl ethers of various thiophenols (or phenols) can be obtained by the more sequential process as shown in Scheme 2 [59]. Use of mixed (Cl/F
- sulfides [89][90][91][92]. It is well known that the reaction of non-activated aryl halides with phenols, thiophenols and amines are catalyzed effectively by copper (Ullmann reaction). L. M. Yagupol’skii [93][94][95][96][97] developed a related protocol for trifluoromethylsulfanylation of aromatic and
- -phenols, and diaryl disulfides with perfluoroalkyl iodides in liquid ammonia under UV irradiation Kornblum’s work on nucleophilic substitution in alkyl halides [134][135][136][137] and Bunnett’s reactions with non-activated aromatic substrates [138][139][140][141][142] (under UV irradiation) introduced
Graphical Abstract
Figure 1: Examples of industrial fluorine-containing bio-active molecules.
Figure 2: CF3(S)- and CF3(O)-containing pharmacologically active compounds.
Figure 3: Hypotensive candidates with SRF and SO2RF groups – analogues of Losartan and Nifedipin.
Figure 4: The variety of the pharmacological activity of RFS-substituted compounds.
Figure 5: Recent examples of compounds containing RFS(O)n-groups [12-18].
Scheme 1: Fluorination of ArSCCl3 to corresponding ArSCF3 derivatives. For references see: a[38-43]; b[41,42]; c[43]; d[44]; e[38-43,45-47]; f[38-43,48,49]; g...
Scheme 2: Preparation of aryl pentafluoroethyl sulfides.
Scheme 3: Mild fluorination of the aryl SCF2Br derivatives.
Scheme 4: HF fluorinations of aryl α,α,β-trichloroisobutyl sulfide at various conditions.
Scheme 5: Monofluorination of α,α-dichloromethylene group.
Scheme 6: Electrophilic substitution of phenols with CF3SCl [69].
Scheme 7: Introduction of SCF3 groups into activated phenols [71-74].
Scheme 8: Preparation of tetrakis(SCF3)-4-methoxyphenol [72].
Scheme 9: The interactions of resorcinol and phloroglucinol derivatives with RFSCl.
Scheme 10: Reactions of anilines with CF3SCl.
Scheme 11: Trifluoromethylsulfanylation of anilines with electron-donating groups in the meta position [74].
Scheme 12: Reaction of benzene with CF3SCl/CF3SO3H [77].
Scheme 13: Reactions of trifluoromethyl sulfenyl chloride with aryl magnesium and -mercury substrates.
Scheme 14: Reactions of pyrroles with CF3SCl.
Scheme 15: Trifluoromethylsulfanylation of indole and indolizines.
Scheme 16: Reactions of N-methylpyrrole with CF3SCl [80,82].
Scheme 17: Reactions of furan, thiophene and selenophene with CF3SCl.
Scheme 18: Trifluoromethylsulfanylation of imidazole and thiazole derivatives [83].
Scheme 19: Trifluoromethylsulfanylation of pyridine requires initial hydride reduction.
Scheme 20: Introduction of additional RFS-groups into heterocyclic compounds in the presence of CF3SO3H.
Scheme 21: Introduction of additional RFS-groups into pyrroles [82,87].
Scheme 22: By-products in reactions of pyrroles with CF3SCl [82].
Scheme 23: Reaction of aromatic iodides with CuSCF3 [93,95].
Scheme 24: Reaction of aromatic iodides with RFZCu (Z = S, Se), RF = CF3, C6F5 [93,95,96].
Scheme 25: Side reactions during trifluoromethylsulfanylation of aromatic iodides with CF3SCu [98].
Scheme 26: Reactions with in situ generated CuSCF3.
Scheme 27: Perfluoroalkylthiolation of aryl iodides with bulky RFSCu [105].
Scheme 28: In situ formation and reaction of RFZCu with aryl iodides.
Figure 6: Examples of compounds obtained using in situ generated RFZCu methodology [94].
Scheme 29: Introduction of SCF3 group into aromatics via difluorocarbene.
Scheme 30: Tetrakis(dimethylamino)ethylene dication trifluoromethyl thiolate as a stable reagent for substitut...
Scheme 31: The use of CF2=S/CsF or (CF3S)2C=S/CsF for the introduction of CF3S groups into fluorinated heteroc...
Scheme 32: One-pot synthesis of ArSCF3 from ArX, CCl2=S and KF.
Scheme 33: Reaction of aromatics with CF3S− Kat+ [115].
Scheme 34: Reactions of activated aromatic chlorides with AgSCF3/KI.
Scheme 35: Comparative CuSCF3/KI and Hg(SCF3)2/KI reactions.
Scheme 36: Me3SnTeCF3 – a reagent for the introduction of the TeCF3 group.
Scheme 37: Sandmeyer reactions with CuSCF3.
Scheme 38: Reactions of perfluoroalkyl iodides with alkali and organolithium reagents.
Scheme 39: Perfluoroalkylation with preliminary breaking of the disulfide bond.
Scheme 40: Preparation of RFS-substituted anilines from dinitrodiphenyl disulfides.
Scheme 41: Photochemical trifluoromethylation of 2,4,6-trimercaptochlorobenzene [163].
Scheme 42: Putative process for the formation of B, C and D.
Scheme 43: Trifluoromethylation of 2-mercapto-4-hydroxy-6-trifluoromethylyrimidine [145].
Scheme 44: Deactivation of 2-mercapto-4-hydroxypyrimidines S-centered radicals.
Scheme 45: Perfluoroalkylation of thiolates with CF3Br under UV irradiation.
Scheme 46: Catalytic effect of methylviologen for RF• generation.
Scheme 47: SO2−• catalyzed trifluoromethylation.
Scheme 48: Electrochemical reduction of CF3Br in the presence of SO2 [199,200].
Scheme 49: Participation of SO2 in the oxidation of ArSCF3−•.
Scheme 50: Electron transfer cascade involving SO2 and MV.
Scheme 51: Four stages of the SRN1 mechanism for thiol perfluoroalkylation.
Scheme 52: A double role of MV in the catalysis of RFI reactions with aryl thiols.
Scheme 53: Photochemical reaction of pentafluoroiodobenzene with trifluoromethyl disulfide.
Scheme 54: N- Trifluoromethyl-N-nitrosobenzene sulfonamide – a source of CF3• radicals [212,213].
Scheme 55: Radical trifluoromethylation of organic disulfides with ArSO2N=NCF3.
Scheme 56: Barton’s S-perfluoroalkylation reactions [216].
Scheme 57: Decarboxylation of thiohydroxamic esters in the presence of C6F13I.
Scheme 58: Reactions of thioesters of trifluoroacetic and trifluoromethanesulfonic acids in the presence of ar...
Scheme 59: Perfluoroalkylation of polychloropyridine thiols with xenon perfluorocarboxylates or XeF2 [222,223].
Scheme 60: Interaction of Xe(OCORF)2 with nitroaryl disulfide [227].
Scheme 61: Bi(CF3)3/Cu(OCOCH3)2 trifluoromethylation of thiophenolate [230].
Scheme 62: Reaction of fluorinated carbanions with aryl sulfenyl chlorides.
Scheme 63: Reaction of methyl perfluoromethacrylate with PhSCl in the presence of fluoride.
Scheme 64: Reactions of ArSCN with potassium and magnesium perfluorocarbanions [237].
Scheme 65: Reactions of RFI with TDAE and organic disulfides [239,240].
Scheme 66: Decarboxylation of perfluorocarboxylates in the presence of disulfides [245].
Scheme 67: Organization of a stable form of “CF3−” anion in the DMF.
Scheme 68: Silylated amines in the presence of fluoride can deprotonate fluoroform for reaction with disulfide...
Figure 7: Other examples of aminomethanols [264].
Scheme 69: Trifluoromethylation of diphenyl disulfide with PhSO2CF3/t-BuOK.
Scheme 70: Amides of trifluoromethane sulfinic acid are sources of CF3− anion.
Scheme 71: Trifluoromethylation of various thiols using “hyper-valent” iodine (III) reagent [279].
Scheme 72: Trifluoromethylation of p-nitrothiophenolate with diaryl CF3 sulfonium salts [280].
Scheme 73: Trifluoromethyl transfer from dibenzo (CF3)S-, (CF3)Se- and (CF3)Te-phenium salts to thiolates [283].
Scheme 74: Multi-stage paths for synthesis of dibenzo-CF3-thiophenium salts [61].
Shelf-stable electrophilic trifluoromethylating reagents: A brief historical perspective
- Norio Shibata,
- Andrej Matsnev and
- Dominique Cahard
Beilstein J. Org. Chem. 2010, 6, No. 65, doi:10.3762/bjoc.6.65
- phosphides (MPPh2) gave only trace amounts of the trifluoromethylated product [34][35]. The reaction of phenols with reagent 35 was investigated. From 2,4,6-trimethylphenol, the expected 1,3,5-trimethyl-2-(trifluoromethoxy)benzene was obtained only in poor yields in the range 4–15%. The trifluoromethylation
- was carried out in the presence of sodium hydride in DMF at different temperatures and occurred preferentially at the ortho- and para-positions of the aromatic ring (Scheme 31). Other substituted phenols were used as substrates under conditions yielding only C-trifluoromethylated products [36
- ]. Although O-trifluoromethylation of phenols still remains an unsolved problem, the trifluoromethylation of aliphatic alcohols is now possible as a result of the efforts of Togni and co-workers who discovered that the transfer of a CF3 group to an alcohol oxygen atom could be achieved in the presence of zinc
Graphical Abstract
Scheme 1: Preparation of the first electrophilic trifluoromethylating reagent and its reaction with a thiophe...
Scheme 2: Synthetic routes to S-CF3 and Se-CF3 dibenzochalcogenium salts.
Scheme 3: Synthesis of (trifluoromethyl)dibenzotellurophenium salts.
Scheme 4: Nitration of (trifluoromethyl)dibenzochalcogenium salts.
Scheme 5: Synthesis of a sulphonium salt with a bridged oxygen.
Scheme 6: Reactivity of (trifluoromethyl)dibenzochalcogenium salts.
Scheme 7: Pd(II)-Catalyzed ortho-trifluoromethylation of heterocycle-substituted arenes by Umemoto’s reagents....
Scheme 8: Mild electrophilic trifluoromethylation of β-ketoesters and silyl enol ethers.
Scheme 9: Enantioselective electrophilic trifluoromethylation of β-ketoesters.
Scheme 10: Preparation of water-soluble S-(trifluoromethyl)dibenzothiophenium salts.
Scheme 11: Method for large-scale preparation of S-(trifluoromethyl)dibenzothiophenium salts.
Scheme 12: Triflic acid catalyzed synthesis of 5-(trifluoromethyl)thiophenium salts.
Scheme 13: Trifluoromethylation of β-ketoesters and dicyanoalkylidenes by S-(trifluoromethyl)benzothiophenium ...
Scheme 14: Synthesis of chiral S-(trifluoromethyl)benzothiophenium salt 18 and attempt of enantioselective tri...
Scheme 15: Synthesis of O-(trifluoromethyl)dibenzofuranium salts.
Scheme 16: Photochemical O- and N-trifluoromethylation by 20b.
Scheme 17: Thermal O-trifluoromethylation of phenol by diazonium salt 19a. Effect of the counteranion.
Scheme 18: Thermal O- and N-trifluoromethylations.
Scheme 19: Method of preparation of S-(trifluoromethyl)diphenylsulfonium triflates.
Scheme 20: Reactivity of some S-(trifluoromethyl)diarylsulfonium triflates.
Scheme 21: One-pot synthesis of S-(trifluoromethyl)diarylsulfonium triflates.
Scheme 22: One-pot synthesis of Umemoto’s type reagents.
Scheme 23: Preparation of sulfonium salts by transformation of CF3− into CF3+.
Scheme 24: Selected reactions with the new Yagupolskii reagents.
Scheme 25: Synthesis of heteroaryl-substituted sulfonium salts.
Scheme 26: First neutral S-CF3 reagents.
Scheme 27: Synthesis of Togni reagents. aYield for the two-step procedure.
Scheme 28: Trifluoromethylation of C-nucleophiles with 37.
Scheme 29: Selected examples of trifluoromethylation of S-nucleophiles with 37.
Scheme 30: Selected examples of trifluoromethylation of P-nucleophiles with 35 and 37.
Scheme 31: Trifluoromethylation of 2,4,6-trimethylphenol with 35.
Scheme 32: Examples of O-trifluoromethylation of alcohols with 35 in the presence of 1 equiv of Zn(NTf2)2.
Scheme 33: Formation of trifluoromethyl sulfonates from sulfonic acids and 35.
Scheme 34: Organocatalytic α-trifluoromethylation of aldehydes with 37.
Scheme 35: Synthesis of reagent 42 and mechanism of trifluoromethylation.
Scheme 36: Trifluoromethylation of β-ketoesters and dicyanoalkylidenes with 42.
Pd-catalyzed decarboxylative Heck vinylation of 2-nitrobenzoates in the presence of CuF2
- Lukas J. Gooßen,
- Bettina Zimmermann and
- Thomas Knauber
Beilstein J. Org. Chem. 2010, 6, No. 43, doi:10.3762/bjoc.6.43
- ][18]. We developed a process in which benzoic acids are activated by esterification with electron-poor phenols with the loss of water [19]. The esters are then subjected to a decarbonylative Heck reaction to yield vinyl arenes, CO and the phenols, which can be used in further reaction cycles. In a
Graphical Abstract
Scheme 1: Proposed mechanism for the decarboxylative Heck reaction.
Molecular recognition of organic ammonium ions in solution using synthetic receptors
- Andreas Späth and
- Burkhard König
Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32
Graphical Abstract
Figure 1: Biologically important amines and quaternary ammonium salts: histamine (1), dopamine (2) and acetyl...
Figure 2: Crown ether 18-crown-6.
Figure 3: Conformations of 18-crown-6 (4) in solvents of different polarity.
Figure 4: Binding topologies of the ammonium ion depending on the crown ring size.
Figure 5: A “pseudorotaxane” structure consisting of 24-crown-8 and a secondary ammonium ion (5); R = Ph.
Figure 6: Typical examples of azacrown ethers, cryptands and related aza macrocycles.
Figure 7: Binding of ammonium to azacrown ethers and cryptands [111-113].
Figure 8: A 19-crown-6-ether with decalino blocking groups (11) and a thiazole-dibenzo-18-crown-6-ether (12).
Figure 9: 1,3-Bis(6-oxopyridazin-1-yl)propane derivatives 13 and 14 by Campayo et al.
Figure 10: Fluorescent azacrown-PET-sensors based on coumarin.
Figure 11: Two different pyridino-cryptands (17 and 18) compared to a pyridino-crown (19); chiral ammonium ion...
Figure 12: Pyridino-18-crown-6 ligand (21), a similar acridino-18-crown-6 ligand (22) and a structurally relat...
Figure 13: Ciral pyridine-azacrown ether receptors 24.
Figure 14: Chiral 15-crown-5 receptors 26 and an analogue 18-crown-6 ligand 27 derived from amino alcohols.
Figure 15: C2-symmetric chiral 18-crown-6 amino alcohol derivatives 28 and related macrocycles.
Figure 16: Macrocycles with diamide-diester groups (30).
Figure 17: C2-symmetric chiral aza-18-crown-6 ethers (31) with phenethylamine residues.
Figure 18: Chiral C-pivot p-methoxy-phenoxy-lariat ethers.
Figure 19: Chiral lariat crown ether 34.
Figure 20: Sucrose-based chiral crown ether receptors 36.
Figure 21: Permethylated fructooligosaccharide 37 showing induced-fit chiral recognition.
Figure 22: Biphenanthryl-18-crown-6 derivative 38.
Figure 23: Chiral lariat crown ethers derived from binol by Fuji et al.
Figure 24: Chiral phenolic crown ether 41 with “aryl chiral barriers” and guest amines.
Figure 25: Chiral bis-crown receptor 43 with a meso-ternaphthalene backbone.
Figure 26: Chromogenic pH-dependent bis-crown chemosensor 44 for diamines.
Figure 27: Triamine guests for binding to receptor 44.
Figure 28: Chiral bis-crown phenolphthalein chemosensors 46.
Figure 29: Crown ether amino acid 47.
Figure 30: Luminescent receptor 48 for bis-alkylammonium guests.
Figure 31: Luminescent CEAA (49a), a bis-CEAA receptor for amino acids (49b) and the structure of lysine bindi...
Figure 32: Luminescent CEAA tripeptide for binding small peptides.
Figure 33: Bis crown ether 51a self assembles co-operatively with C60-ammonium ion 51b.
Figure 34: Triptycene-based macrotricyclic dibenzo-[24]-crown-8 ether host 52 and guests.
Figure 35: Copper imido diacetic acid azacrown receptor 53a and the suggested His-Lys binding motif; a copper ...
Figure 36: Urea (54) and thiourea (55) benzo crown receptor for transport and extraction of amino acids.
Figure 37: Crown pyryliums ion receptors 56 for amino acids.
Figure 38: Ditopic sulfonamide bridged crown ether receptor 57.
Figure 39: Luminescent peptide receptor 58.
Figure 40: Luminescent receptor 59 for the detection of D-glucosamine hydrochloride in water/ethanol and lumin...
Figure 41: Guanidinium azacrown receptor 61 for simple amino acids and ditopic receptor 62 with crown ether an...
Figure 42: Chiral bicyclic guanidinium azacrown receptor 63 and similar receptor 64 for the enantioselective t...
Figure 43: Receptors for zwitterionic species based on luminescent CEAAs.
Figure 44: 1,10-Azacrown ethers with sugar podand arms and the anticancer agent busulfan.
Figure 45: Benzo-18-crown-6 modified β-cyclodextrin 69 and β-cyclodextrin functionalized with diaza-18-crown-6...
Figure 46: Receptors for colorimetric detection of primary and secondary ammonium ions.
Figure 47: Porphyrine-crown-receptors 72.
Figure 48: Porphyrin-crown ether conjugate 73 and fullerene-ammonium ion guest 74.
Figure 49: Calix[4]arene (75a), homooxocalix[4]arene (75b) and resorcin[4]arene (75c) compared (R = H, alkyl c...
Figure 50: Calix[4]arene and ammonium ion guest (R = H, alkyl, OAcyl etc.), possible binding sites; A: co-ordi...
Figure 51: Typical guests for studies with calixarenes and related molecules.
Figure 52: Lower rim modified p-tert-butylcalix[5]arenes 82.
Figure 53: The first example of a water soluble calixarene.
Figure 54: Sulfonated water soluble calix[n]arenes that bind ammonium ions.
Figure 55: Displacement assay for acetylcholine (3) with a sulfonato-calix[6]arene (84b).
Figure 56: Amino acid inclusion in p-sulfonatocalix[4]arene (84a).
Figure 57: Calixarene receptor family 86 with upper and lower rim functionalization.
Figure 58: Calix[6]arenes 87 with one carboxylic acid functionality.
Figure 59: Sulfonated calix[n]arenes with mono-substitution at the lower rim systematically studied on their r...
Figure 60: Cyclotetrachromotropylene host (91) and its binding to lysine (81c).
Figure 61: Calixarenes 92 and 93 with phosphonic acids groups.
Figure 62: Calix[4]arene tetraphosphonic acid (94a) and a double bridged analogue (94b).
Figure 63: Calix[4]arene tetraphosphonic acid ester (92c) for surface recognition experiments.
Figure 64: Calixarene receptors 95 with α-aminophosphonate groups.
Figure 65: A bridged homocalix[3]arene 95 and a distally bridged homocalix[4]crown 96.
Figure 66: Homocalix[3]arene ammonium ion receptor 97a and the Reichardt’s dye (97b) for colorimetric assays.
Figure 67: Chromogenic diazo-bridged calix[4]arene 98.
Figure 68: Calixarene receptor 99 by Huang et al.
Figure 69: Calixarenes 100 reported by Parisi et al.
Figure 70: Guest molecules for inclusion in calixarenes 100: DAP × 2 HCl (101a), APA (101b) and Lys-OMe × 2 HC...
Figure 71: Different N-linked peptido-calixarenes open and with glycol chain bridges.
Figure 72: (S)-1,1′-Bi-2-naphthol calixarene derivative 104 published by Kubo et al.
Figure 73: A chiral ammonium-ion receptor 105 based on the calix[4]arene skeleton.
Figure 74: R-/S-phenylalaninol functionalized calix[6]arenes 106a and 106b.
Figure 75: Capped homocalix[3]arene ammonium ion receptor 107.
Figure 76: Two C3 symmetric capped calix[6]arenes 108 and 109.
Figure 77: Phosphorous-containing rigidified calix[6]arene 110.
Figure 78: Calix[6]azacryptand 111.
Figure 79: Further substituted calix[6]azacryptands 112.
Figure 80: Resorcin[4]arene (75c) and the cavitands (113).
Figure 81: Tetrasulfonatomethylcalix[4]resorcinarene (114).
Figure 82: Resorcin[4]arenes (115a/b) and pyrogallo[4]arenes (115c, 116).
Figure 83: Displacement assay for acetylcholine (3) with tetracyanoresorcin[4]arene (117).
Figure 84: Tetramethoxy resorcinarene mono-crown-5 (118).
Figure 85: Components of a resorcinarene based displacement assay for ammonium ions.
Figure 86: Chiral basket resorcin[4]arenas 121.
Figure 87: Resorcinarenes with deeper cavitand structure (122).
Figure 88: Resorcinarene with partially open deeper cavitand structure (123).
Figure 89: Water-stabilized deep cavitands with partially structure (124, 125).
Figure 90: Charged cavitands 126 for tetralkylammonium ions.
Figure 91: Ditopic calix[4]arene receptor 127 capped with glycol chains.
Figure 92: A calix[5]arene dimer for diammonium salt recognition.
Figure 93: Calixarene parts 92c and 129 for the formation molecular capsules.
Figure 94: Encapsulation of a quaternary ammonium cation by two resorcin[4]arene molecules (NMe4+@[75c]2 × Cl−...
Figure 95: Encapsulation of a quaternary ammonium cation by six resorcin[4]arene molecules (NMe3D+@[130]6 × Cl−...
Figure 96: Structure and schematic of cucurbit[6]uril (CB[6], 131a).
Figure 97: Cyclohexanocucurbit[6]uril (CB′[6], 132) and the guest molecule spermine (133).
Figure 98: α,α,δ,δ-Tetramethylcucurbit[6]uril (134).
Figure 99: Structure of the cucurbituril-phthalhydrazide analogue 135.
Figure 100: Organic cavities for the displacement assay for amine differentiation.
Figure 101: Displacement assay methodology for diammonium- and related guests involving cucurbiturils and some ...
Figure 102: Nor-seco-Cucurbituril (±)-bis-ns-CB[6] (140) and guest molecules.
Figure 103: The cucurbit[6]uril based complexes 141 for chiral discrimination.
Figure 104: Cucurbit[7]uril (131c) and its ferrocene guests (142) opposed.
Figure 105: Cucurbit[7]uril (131c) guest inclusion and representative guests.
Figure 106: Cucurbit[7]uril (131c) binding to succinylcholine (145) and different bis-ammonium and bis-phosphon...
Figure 107: Paraquat-cucurbit[8]uril complex 149.
Figure 108: Gluconuril-based ammonium receptors 150.
Figure 109: Examples of clefts (151a), tweezers (151b, 151c, 151d) and clips (151e).
Figure 110: Kemp’s triacid (152a), on example of Rebek’s receptors (152b) and guests.
Figure 111: Amino acid receptor (154) by Rebek et al.
Figure 112: Hexagonal lattice designed hosts by Bell et al.
Figure 113: Bell’s amidinium receptor (156) and the amidinium ion (157).
Figure 114: Aromatic phosphonic acids.
Figure 115: Xylene phosphonates 159 and 160a/b for recognition of amines and amino alcohols.
Figure 116: Bisphosphonate recognition motif 161 for a colorimetric assay with alizarin complexone (163) for ca...
Figure 117: Bisphosphonate/phosphate clip 164 and bisphosphonate cleft 165.
Figure 118: N-Methylpyrazine 166a, N-methylnicotinamide iodide (166b) and NAD+ (166c).
Figure 119: Bisphosphate cavitands.
Figure 120: Bisphosphonate 167 of Schrader and Finocchiaro.
Figure 121: Tweezer 168 for noradrenaline (80b).
Figure 122: Different tripods and heparin (170).
Figure 123: Squaramide based receptors 172.
Figure 124: Cage like NH4+ receptor 173 of Kim et al.
Figure 125: Ammonium receptors 174 of Chin et al.
Figure 126: 2-Oxazolin-based ammonium receptors 175a–d and 176 by Ahn et al.
Figure 127: Racemic guest molecules 177.
Figure 128: Tripods based on a imidazole containing macrocycle (178) and the guest molecules employed in the st...
Figure 129: Ammonium ion receptor 180.
Figure 130: Tetraoxa[3.3.3.3]paracyclophanes 181 and a cyclophanic tetraester (182).
Figure 131: Peptidic bridged paraquat-cyclophane.
Figure 132: Shape-selective noradrenaline host.
Figure 133: Receptor 185 for binding of noradrenaline on surface layers from Schrader et al.
Figure 134: Tetraphosphonate receptor for binding of noradrenaline.
Figure 135: Tetraphosphonate 187 of Schrader and Finocchiaro.
Figure 136: Zinc-Porphyrin ammonium-ion receptors 188 and 189 of Mizutani et al.
Figure 137: Zinc porphyrin receptor 190.
Figure 138: Zinc porphyrin receptors 191 capable of amino acid binding.
Figure 139: Zinc-porphyrins with amino acid side chains for stereoinduction.
Figure 140: Bis-zinc-bis-porphyrin based on Tröger’s base 193.
Figure 141: BINAP-zinc-prophyrin derivative 194 and it’s guests.
Figure 142: Bisaryl-linked-zinc-porphyrin receptors.
Figure 143: Bis-zinc-porphyrin 199 for diamine recognition and guests.
Figure 144: Bis-zinc-porphyrin crown ether 201.
Figure 145: Bis-zinc-porphyrin 202 for stereodiscrimination (L = large substituent; S = small substituent).
Figure 146: Bis-zinc-porphyrin[3]rotaxane and its copper complex and guests.
Figure 147: Dien-bipyridyl ligand 206 for co-ordination of two metal atoms.
Figure 148: The ligand and corresponding tetradentate co-complex 207 serving as enantioselective receptor for a...
Figure 149: Bis(oxazoline)–copper(II) complex 208 for the recognition of amino acids in aqueous solution.
Figure 150: Zinc-salen-complexes 209 for the recognition tertiary amines.
Figure 151: Bis(oxazoline)–copper(II) 211 for the recognition of amino acids in aqueous solution.
Figure 152: Zn(II)-complex of a C2 terpyridine crown ether.
Figure 153: Displacement assay and receptor for aspartate over glutamate.
Figure 154: Chiral complex 214 for a colorimetric displacement assay for amino acids.
Figure 155: Metal complex receptor 215 with tripeptide side arms.
Figure 156: A sandwich complex 216 and its displaceable dye 217.
Figure 157: Lanthanide complexes 218–220 for amino acid recognition.
Figure 158: Nonactin (221), valinomycin (222) and vancomycin (223).
Figure 159: Monesin (224a) and a chiral analogue for enantiodiscrimination of ammonium guests (224b).
Figure 160: Chiral podands (226) compared to pentaglyme-dimethylether (225) and 18-crown-6 (4).
Figure 161: Lasalocid A (228).
Figure 162: Lasalocid derivatives (230) of Sessler et al.
Figure 163: The Coporphyrin I tetraanion (231).
Figure 164: Linear and cyclic peptides for ammonium ion recognition.
Figure 165: Cyclic and bicyclic depsipeptides for ammonium ion recognition.
Figure 166: α-Cyclodextrin (136a) and novocaine (236).
Figure 167: Helical diol receptor 237 by Reetz and Sostmann.
Figure 168: Ammonium binding spherand by Cram et al. (238a) and the cyclic[6]metaphenylacetylene 238b in compar...
Figure 169: Receptor for peptide backbone and ammonium binding (239).
Figure 170: Anion sensor principle with 3-hydroxy-2-naphthanilide of Jiang et al.
Figure 171: 7-bromo-3-hydroxy-N-(2-hydroxyphenyl)naphthalene 2-carboxamide (241) and its amine binding.
Figure 172: Naturally occurring catechins with affinity to quaternary ammonium ions.
Figure 173: Spiropyran (244) and merocyanine form (244a) of the amino acid receptors of Fuji et al.
Figure 174: Coumarin aldehyde (245) and its iminium species with amino acid bound (245a) by Glass et al.
Figure 175: Coumarin aldehyde appended with boronic acid.
Figure 176: Quinolone aldehyde dimers by Glass et al.
Figure 177: Chromogenic ammonium ion receptors with trifluoroacetophenone recognition motifs.
Figure 178: Chromogenic ammonium ion receptor with trifluoroacetophenone recognition motif bound on different m...
Solvent-free and time-efficient Suzuki–Miyaura reaction in a ball mill: the solid reagent system KF–Al2O3 under inspection
- Franziska Bernhardt,
- Ronald Trotzki,
- Tony Szuppa,
- Achim Stolle and
- Bernd Ondruschka
Beilstein J. Org. Chem. 2010, 6, No. 7, doi:10.3762/bjoc.6.7
- -prepared SRS either in air atmosphere or in a desiccator over KOH are possible. Removal of residual water by calcination for 2 h at 300 °C afforded a strongly deactivated material, confirming the earlier studies on the application of calcinated KF–Al2O3 in the O-methylation of phenols [21]. For obtaining
Graphical Abstract
Scheme 1: Suzuki–Miyaura reaction of phenylboronic acid (1) with aryl bromides 2 yielding substituted biaryls ...
Figure 1: Results of the Suzuki–Miyaura reaction of phenylboronic acid (1) with p-bromoacetophenone (2a; cf. Scheme 1...
Figure 2: Results of the Suzuki–Miyaura reaction according to Scheme 1 assisted by pure aluminas [5 g SRS1–3: cf. Table 2; b...
Figure 3: Influence of Pd(OAc)2 concentration on the results of the Suzuki–Miyaura reaction of phenylboronic ...
Figure 4: Results of the Suzuki–Miyaura reaction according to Scheme 1 assisted by KF-loaded aluminas [5 g SRS1a–4a, ...
Figure 5: Dependence of the yield of Suzuki–Miyaura cross-coupling product (Scheme 1) from water content (Karl-Fische...
A review of new developments in the Friedel–Crafts alkylation – From green chemistry to asymmetric catalysis
- Magnus Rueping and
- Boris J. Nachtsheim
Beilstein J. Org. Chem. 2010, 6, No. 6, doi:10.3762/bjoc.6.6
- . Interestingly, the application of the in situ generated Mo(IV)-catalyst Mo(acac)2(SbF6)2 resulted exclusively in C-allylated arenes, while the catalyst precursor Mo(acac)2Cl2 gave the O-allylated phenols as major products. Remarkably the reaction between p-cresol 58 and linear or branched allyl alcohols 54a or
- developed by using diruthenium complexes 85a and 85b (Scheme 34B) [95]. The reaction proceeded smoothly and yields of the propargylated arenes 89 were even higher when only small amounts of the catalyst were used. Interestingly, if phenols and naphthols 91 were applied as nucleophiles, both Cα- and Cγ
Graphical Abstract
Scheme 1: AlCl3-mediated reaction between amyl chloride and benzene as developed by Friedel and Crafts.
Figure 1: Most often used metal salts for catalytic FC alkylations and hydroarylations of arenes.
Figure 2: 1,1-diarylalkanes with biological activity.
Scheme 2: Alkylating reagents and side products produced.
Scheme 3: Initially reported TeCl4-mediated FC alkylation of 1-penylethanol with toluene.
Scheme 4: Sc(OTf)3-catalyzed FC benzylation of arenes.
Scheme 5: Reductive FC alkylation of arenes with arenecarbaldehydes.
Scheme 6: Iron(III)-catalyzed FC benzylation of arenes and heteroarenes.
Scheme 7: A gold(III)-catalyzed route to beclobrate.
Scheme 8: Catalytic FC-type alkylations of 1,3-dicarbonyl compounds.
Scheme 9: Iron(III)-catalyzed synthesis of phenprocoumon.
Scheme 10: Bi(OTf)3-catalyzed FC alkylation of benzyl alcohols developed by Rueping et al.
Scheme 11: (A) Bi(OTf)3-catalyzed intramolecular FC alkylation as an efficient route to substituted fulvenes. ...
Scheme 12: FC-type glycosylation of 1,2-dimethylindole and trimethoxybenzene.
Scheme 13: FC alkylation with highly reactive ferrocenyl- and benzyl alcohols. The reaction proceeds even with...
Scheme 14: Reductive FC alkylation of arenes with benzaldehyde and acetophenone catalyzed by the Ir-carbene co...
Scheme 15: Formal synthesis of 1,1-diarylalkanes from benzyl alcohols and styrenes.
Scheme 16: (A) Mo-catalyzed hydroarylation of styrenes and cyclohexenes. (B) Hydroalkylation–cyclization casca...
Scheme 17: Bi(III)-catalyzed hydroarylation of styrenes with arenes and heteroarenes.
Scheme 18: BiCl3-catalyzed ene/FC alkylation reaction cascade – A fast access to highly arylated dihydroindene...
Scheme 19: Au(I)/Ag(I)-catalyzed hydroarylation of indoles with styrenes, aliphatic and cyclic alkenes.
Scheme 20: First transition-metal-catalyzed ortho-hydroarylation developed by Beller et al.
Scheme 21: (A) Ti(IV)-mediated rearrangement of an N-benzylated aniline to the corresponding ortho-alkylated a...
Scheme 22: Dibenzylation of aniline gives potentially useful amine-based ligands in a one-step procedure.
Scheme 23: FC-type alkylations with allyl alcohols as alkylating reagents – linear vs. branched product format...
Scheme 24: (A) First catalytic FC allylation and cinnamylation using allyl alcohols and its derivatives. (B) E...
Scheme 25: FC allylation/cyclization reaction yielding substituted chromanes.
Scheme 26: Synthesis of (all-rac)-α-tocopherol utilizing Lewis- and strong Brønsted-acids.
Scheme 27: Au(III)-catalyzed cinnamylation of arenes.
Scheme 28: “Exhaustive” allylation of benzene-1,3,5-triol.
Scheme 29: Palladium-catalyzed allylation of indole.
Scheme 30: Pd-catalyzed synthesis of pyrroloindoles from L-tryptophane.
Scheme 31: Ru(IV)-catalyzed allylation of indole and pyrroles with unique regioselectivity.
Scheme 32: Silver(I)-catalyzed intramolecular FC-type allylation of arenes and heteroarenes.
Scheme 33: FC-type alkylations of arenes using propargyl alcohols.
Scheme 34: (A) Propargylation of arenes with stoichiometric amounts of the Ru-allenylidene complex 86. (B) Fir...
Scheme 35: Diruthenium-catalyzed formation of chromenes and 1H-naphtho[2,1-b]pyrans.
Scheme 36: Rhenium(V)-catalyzed FC propargylations as a first step in the total synthesis of podophyllotoxin, ...
Scheme 37: Scandium-catalyzed arylation of 3-sulfanyl- and 3-selanylpropargyl alcohols.
Scheme 38: Synthesis of 1,3-diarylpropynes via direct coupling of propargyl trichloracetimidates and arenes.
Scheme 39: Diastereoselective substitutions of benzyl alcohols.
Scheme 40: (A) First diastereoselective FC alkylations developed by Bach et al. (B) anti-Selective FC alkylati...
Scheme 41: Diastereoselective AuCl3-catalyzed FC alkylation.
Scheme 42: Bi(OTf)3-catalyzed alkylation of α-chiral benzyl acetates with silyl enol ethers.
Scheme 43: Bi(OTf)3-catalyzed diastereoselective substitution of propargyl acetates.
Scheme 44: Nucelophilic substitution of enantioenriched ferrocenyl alcohols.
Scheme 45: First catalytic enantioselective propargylation of arenes.
Ring-alkyl connecting group effect on mesogenic properties of p-carborane derivatives and their hydrocarbon analogues
- Aleksandra Jankowiak,
- Piotr Kaszynski,
- William R. Tilford,
- Kiminori Ohta,
- Adam Januszko,
- Takashi Nagamine and
- Yasuyuki Endo
Beilstein J. Org. Chem. 2009, 5, No. 83, doi:10.3762/bjoc.5.83
- [33] and 4-pentylphenol (Scheme 2) according to a recently described procedure [2]. The two series of tetraesters 19 and 20 were prepared from the appropriate dicarboxylic acid 22 and phenols 23 and 24, respectively. p-Carborane-1,12-dicarboxylic acid 22A and terephthalic acid (22D) were converted to
- the corresponding acid chlorides using PCl5 and then reacted with phenols in the presence of a base. The previously described method [2] for the preparation of esters of bicyclo[2.2.2]octane-1,4-dicarboxylic acid (22C) was unsuccessful and the desired esters 19C and 20C were obtained from the diacid
Graphical Abstract
Figure 1: The molecular structures of 1,12-dicarba-closo-dodecaborane (12-vertex p-carborane, A) and 1,10-dic...
Figure 2: The molecular structures of derivatives 1–20.
Scheme 1: Preparation of diesters 16[n].
Scheme 2: Preparation of esters 18–20.
Scheme 3: Preparation of phenol 24.
Figure 3: Partial DSC trace for 16D[6]. Heating rate 5 K/min.
Figure 4: Optical textures of 16D[6] obtained for the same region of the sample upon cooling: (a) SmA growing...
Figure 5: The change in the clearing temperature ΔTc upon substitution –OCH2– → –CH2CH2– in selected pairs of...
Figure 6: The change in the clearing temperature ΔTc upon replacing of the –OCH2– connecting group with anoth...
Figure 7: Equilibrium ground state geometries (B3LYP/6-31G(d)) for benzene derivatives: ethoxybenzene (25), p...
Iridium-catalyzed asymmetric ring-opening reactions of oxabicyclic alkenes with secondary amine nucleophiles
- Dingqiao Yang,
- Ping Hu,
- Yuhua Long,
- Yujuan Wu,
- Heping Zeng,
- Hui Wang and
- Xiongjun Zuo
Beilstein J. Org. Chem. 2009, 5, No. 53, doi:10.3762/bjoc.5.53
- -catalyzed asymmetric ring-opening of oxabenzonorbornadiene with a wide range of nucleophiles including thiols [10], phenols [11], organoboronic acids [12][13], dialkylzincs [14][15], carboxylates [16], sulfur nucleophiles [17], and various amines [18][19]. In addition to rhodium catalysts, other transition
Graphical Abstract
Scheme 1: Identification of optimal chiral ligand for iridium-catalyzed asymmetric ring-opening of oxabenzono...
Figure 1: ORTEP plot for 3f.
Scheme 2: Proposed mechanism for the ARO of oxabenzonorbornadiene 1a with secondary amine nucleophiles.
A stable enol from a 6-substituted benzanthrone and its unexpected behaviour under acidic conditions
- Marc Debeaux,
- Kai Brandhorst,
- Peter G. Jones,
- Henning Hopf,
- Jörg Grunenberg,
- Wolfgang Kowalsky and
- Hans-Hermann Johannes
Beilstein J. Org. Chem. 2009, 5, No. 31, doi:10.3762/bjoc.5.31
- -substituted phenols is a well known phenomenon in mass spectrometry (the “ortho-effect” see [6]). Next, the enol 4 was treated deliberately under acidic conditions by heating it with phosphoric acid in toluene under reflux. Silica gel was added to the two-phase mixture in order to effect a better contact
Graphical Abstract
Scheme 1: Behaviour of benzanthrone (1) towards phenylmagnesium chloride (a), phenyl lithium (b), and bipheny...
Figure 1: 1H NMR spectra (200 MHz) of 4 in CDCl3 solution and time dependence.
Scheme 2: Proposed mechanism for the formation of 4 and its oxidation to 7.
Scheme 3: Conversion of the enol 4 under acidic conditions and reaction products.
Scheme 4: Proposed mechanism for the formation of spiro compound 11 and bicyclo[4.3.1]decane derivative 12.
Scheme 5: Proposed mechanism for the formation of 13.
Scheme 6: Proposed mechanism for the formation of 18 as a hydride source and further conversion to 7.
Figure 2: Ellipsoid representation (50% level) of compound 7 in the crystal.
Figure 3: Packing diagram of compound 7 viewed parallel to b; hydrogen bonds C-H···O are indicated by dashed ...
Figure 4: Ellipsoid representation (50% level) of compound 11 in the crystal.
Figure 5: Packing diagram of compound 11 viewed perpendicular to the bc plane; hydrogen bonds C-H···π are ind...
Figure 6: Ellipsoid representation (50% level) of compound 13 (d6-DMSO solvate) in the crystal. Hydrogen bond...
Figure 7: Packing diagram of compound 13 viewed parallel to c; DMSO molecules (including their hydrogen bonds...
Synthesis of methylenebisamides using CC- or DCMT- activated DMSO
- Qiang Wang,
- Lili Sun,
- Yu Jiang and
- Chunbao Li
Beilstein J. Org. Chem. 2008, 4, No. 51, doi:10.3762/bjoc.4.51
- reaction of nucleophilic reagents such as amides, alcohols, and phenols with DMSO activated by CC. The amide moiety is an important constituent of many biologically significant compounds. Bisamides are of considerable interest in the synthesis of peptidomimetic compounds [15]. In particular, bisamides are
Graphical Abstract
Scheme 1: Synthesis of N,N′-methylenedibenzamide using CC-activated DMSO.
Scheme 2: Synthesis of N,N′-methylenebisamide using CC-activated DMSO.
Scheme 3: Synthesis of N,N′-methylenedibenzamide using DCMT-activated DMSO.
Scheme 4: Synthesis of N,N′-methylenebisamide using DCMT-activated DMSO.
Scheme 5: Plausible reaction mechanism of amide with CC- or DCMT-activated DMSO.
Diels- Alder reactions using 4,7-dioxygenated indanones as dienophiles for regioselective construction of oxygenated 2,3-dihydrobenz[f]indenone skeleton
- Natsuno Etomi,
- Takuya Kumamoto,
- Waka Nakanishi and
- Tsutomu Ishikawa
Beilstein J. Org. Chem. 2008, 4, No. 15, doi:10.3762/bjoc.4.15
- bromoquinone 12 after modification of the workup protocol without aqueous sodium bicarbonate. The PIFA oxidation of phenols 19 [35] and 20 in the presence of methanol gave the corresponding monoacetals 13 and 14. DAR of indanetrione 8 and 1-methoxy-1,3-butadiene (7) in dichloromethane (CH2Cl2) proceeded
Graphical Abstract
Figure 1: The structure of kinamycins.
Scheme 1: Retrosynthesis of kinamycins.
Scheme 2: Synthesis of quinones 8 and 12 and the acetals 13 and 14. Reagents and conditions: a) P2O5, CH3SO3H...
Figure 2: Selected HMBC correlations (lines) and NOE enhancements (dash) on 21 (a) and on 22 (b).
Scheme 3: DAR of benzyne 10 and furan (9). Reagents and conditions: a) ethylene glycol, PPTS, benzene, reflux...
Figure 3: Selected HMBC correlations (a) and NOE enhancements (b) on the ring-opened product 27.
Figure 4: Transition states supposed for the regioselective DAR via quinone route.
Figure 5: Representative LUMO coeffients of quinones 8 and 12 (a) and their reaction courses with diene 7 (b)....
Scheme 4: The proposed mechanism for the acid-induced ring opening of epoxynaphthalene 29 by Giles et al. [19].
Scheme 5: Supposed reaction pathways for the acid-induced ring opening of 11.
Trifluoromethyl ethers – synthesis and properties of an unusual substituent
- Frédéric R. Leroux,
- Baptiste Manteau,
- Jean-Pierre Vors and
- Sergiy Pazenok
Beilstein J. Org. Chem. 2008, 4, No. 13, doi:10.3762/bjoc.4.13
- recently in detail on the preparation of O-(trifluoromethyl)dibenzofuranium salts 4 [28][29][30][31] and their use as CF3-transfer agents based on studies of Yagupol'skii [32]. The direct O- and N-trifluoromethylation of alcohols, phenols, amines, anilines and pyridines under mild conditions was described
- substituent due to the oxygen lone pairs. Yagupol'skii [57][58] and Sheppard [53][59] provided detailed data on the pKa-values of benzoic acids and phenols which reveal that the trifluoromethoxy group is a moderately electron-withdrawing moiety which resembles a chlorine atom. The pKa values are lowered by
Graphical Abstract
Figure 1: OCF3-bearing pesticides.
Scheme 1: Preparation of trifluoromethyl ethers via a chlorination/fluorination sequence.
Scheme 2: Preparation of trifluoromethyl ethers via an in situ chlorination/fluorination sequence.
Scheme 3: Preparation of trifluoromethyl ethers via chlorothionoformates.
Scheme 4: Preparation of trifluoromethyl ethers via fluoroformates.
Scheme 5: Oxidative desulfurization-fluorination toward trifluoromethyl ethers.
Scheme 6: Mechanism of the oxidative desulfurization-fluorination.
Scheme 7: Umemoto's O-(trifluoromethyl)dibenzofuranium salts 4 as CF3-transfer agents.
Scheme 8: Togni's approach using hypervalent iodine compounds as CF3-transfer agents.
Scheme 9: TAS OCF3 as a nucleophilic OCF3-transfer agent.
Figure 2: Mesomeric structures of the OCF3-group.
Figure 3: Structures of 6 and 7.
Figure 4: Conformational preference of the trifluoromethoxy group on aryl rings.
Scheme 10: Nitration of trifluoromethoxy benzene.
Scheme 11: Synthesis and Nitration of N-Acetyl-(trifluoromethoxy)anilines.
Scheme 12: Bromine/lithium exchange of bromo(trifluoromethoxy)benzenes.
Scheme 13: Metalation of (trifluoromethoxy)benzene.
Scheme 14: Metalation of (trifluoromethoxy)naphthalenes.
Scheme 15: Competition between -CF3- and -OCF3 in Metalation reactions.
Scheme 16: Competition between -F- and -OCF3 in Metalation reactions.
Scheme 17: Metalation of trifluoromethoxyanisoles.
Figure 5: Direction of π-polarization depending on the substituent as described by Schlosser et al. [57].
Scheme 18: Metalation of Bromo(trifluoromethoxy)benzenes.
Scheme 19: Aryne formation from bromo(trifluoromethoxy)phenyllithiums and subsequent Diels-Alder cycloaddition...
Scheme 20: Metalation of (trifluoromethoxy)anilines.
Diastereoselective synthesis of some novel benzopyranopyridine derivatives
- Pradeep K. Mohakhud,
- Sujeet M. R. Kumar,
- Vasanth M. R. Kumar,
- Ravi M. R. Kumar,
- Moses D. R. Babu,
- Vyas D. R. K and
- Om D. R. Reddy
Beilstein J. Org. Chem. 2006, 2, No. 25, doi:10.1186/1860-5397-2-25
- phenols and mesylate derivatives, unexpectedly resulted in cyclodehydration leading to new benzopyrano derivatives, N-substituted-1,2,3,4-tetrahydro[1,3]-dioxolo-[6,7]-5H-[1]benzopyrano [3,4-c]pyridines. The process involves the deprotection of the carbonyl protecting group, and then the cyclization
Graphical Abstract
Figure 1: General structures A & B, Tetrahydro cannabinole derivatives.
Figure 2: General structures C & D, Benzopyrano pyridine derivatives.
Scheme 1: Synthetic sequence to tetrahydropyridine compounds.
Scheme 2: Resolution of enantiomers using D(-) mandelic acid.
Figure 3: Proposed mechanism of tetrahydropyridine formation, Proposed mechanism.
Figure 4: Molecular structure of the mandalate salt.
Figure 5: Structural elucidation.
The Elbs and Boyland- Sims peroxydisulfate oxidations
- E. J. Behrman
Beilstein J. Org. Chem. 2006, 2, No. 22, doi:10.1186/1860-5397-2-22
- to the dihydric phenols (or aminophenols). The yields of products are typically low to moderate, but the simplicity of the reactions frequently recommends their use. Reactions are usually carried out by dissolving the phenol or amine in an alkaline aqueous medium, sometimes with the addition of a co
- (amine)-peroxydisulfate ratio is large. Isolation of the product usually takes advantage of the high water solubility of the intermediate sulfate ester; acidification of the reaction mixture is followed by extraction of the unreacted starting material (in the case of phenols) by an appropriate organic
- yield by peroxydisulfate oxidation of phenols under acid conditions. [9][10] Discussion of some unresolved problems 1. The ortho-para ratio We have previously calculated the energy difference between the ortho- and para- intermediates shown in Scheme 5; it is about 2 kcal mol-1. [4] This calculation
Graphical Abstract
Scheme 1: The Elbs and Boyland-Sims Oxidations.
Scheme 2: The Intermediate in the Boyland-Sims Oxidation
Scheme 3: The Intermediate in the Elbs Oxidation.
Scheme 4: Reaction of Caro's Acid Anion with 2,5-dinitrofluorobenzene.
Scheme 5: Ortho- and para-intermediates for the Elbs Oxidation.
Scheme 6: Reaction of an Elbs Intermediate with the Hydroxide Ion.
Scheme 7: A Catalytic Cycle for Peroxydisulfate Consumption.
Scheme 8: A Non-catalytic cycle for Peroxydisulfate Consumption.
