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Search for "Katritzky salt" in Full Text gives 3 result(s) in Beilstein Journal of Organic Chemistry.
Photoredox catalysis harvesting multiple photon or electrochemical energies
- Mattia Lepori,
- Simon Schmid and
- Joshua P. Barham
Beilstein J. Org. Chem. 2023, 19, 1055–1145, doi:10.3762/bjoc.19.81
Graphical Abstract
Figure 1: Oxidative and reductive activations of organic compounds harvesting photoredox catalysis.
Figure 2: General catalytic cycles of radical ion conPET (left) and radical ion e-PRC (right).
Figure 3: “Beginner’s guide”: comparison between advantages, capacities, and prospectives of conPET and PEC.
Figure 4: A) conPET reductive dehalogenation of aryl halides with PDI. B) Reductive C–H arylation with pyrrol...
Figure 5: A) Chromoselective mono- and disubstitution or polybrominated pyrimidines with pyrroles. B) Sequent...
Figure 6: A) Synthesis of pyrrolo[1,2-a]quinolines. B) Synthesis of ullazines.
Figure 7: A) Reductive phosphorylation of aryl halides via conPET. B) Selected examples from the substrate sc...
Figure 8: A) Reductive dehalogenation of aryl halides via conPET and selected examples from the substrate sco...
Figure 9: A) Reductive C–H arylation of aryl halides via conPET (top) and selected examples from the substrat...
Figure 10: A) Reductive hydrodehalogenation of aryl halides with Mes-Acr-BF4. B) Selected examples from the su...
Figure 11: A) Reductive hydrodechlorination of aryl chlorides with 4-DPAIPN. B) Proposed formation of CO2•−. C...
Figure 12: A) Reductive conPET borylation with 3CzEPAIPN (top) and selected examples from the substrate scope ...
Figure 13: Scale-up of conPET phosphorylation with 3CzEPAIPN.
Figure 14: A) Borylation of 1d. B) Characteristics and structure of PC1 with green and red parts showing the l...
Figure 15: A) Reductive C–H arylation scope with polysulfide conPET (top) and selected examples from the subst...
Figure 16: Scale-up of A) C–H arylation and B) dehaloborylation with polysulfide photocatalysis in continuous-...
Figure 17: A) Formation of [Ir1]0 and [Ir2]0 upon PET between [Ir1]+ and Et3N. B) Mechanism of multi-photon ta...
Figure 18: A) Reductive hydrodehalogenation of aryl halides via multi-photon tandem photocatalysis. B) Selecte...
Figure 19: A) Carbonylative amidation of aryl halides in continuous flow. B) Selected examples from the substr...
Figure 20: A) General scheme for reductive (RQ) and oxidative quenching (OQ) protocols using [FeIII(btz)3](PF6)...
Figure 21: A) Carbonylative amidation of alkyl iodides with [IrIII(ppy)2(dtbbpy)]PF6. B) Selected examples fro...
Figure 22: A) Carboxylative C–N bond cleavage in cyclic amines. B) Selected examples from the substrate scope....
Figure 23: A) Formal reduction of alkenes to alkanes via transfer hydrogenation. B) Selected examples from the...
Figure 24: A) Birch-type reduction of benzenes with PMP-BPI. B) Selected examples from the substrate scope (sc...
Figure 25: Proposed mechanism of the OH− mediated conPET Birch-type reduction of benzene via generation of sol...
Figure 26: Reductive detosylation of N-tosylated amides with Mes-Acr-BF4. B) Selected examples from the substr...
Figure 27: A) Reductive detosylation of N-tosyl amides by dual PRC. B) Selected examples from the substrate sc...
Figure 28: A) Mechanism of the dual PRC based on PET between [Cu(dap)2]+ and DCA. B) Mechanism of the dual PRC...
Figure 29: A) N–O bond cleavage in Weinreb amides with anthracene. B) N–O bond cleavage in Weinreb amides rely...
Figure 30: A) Pentafluorosulfanylation and fluoride elimination. B) Mechanism of the pentafluorosulfanylation ...
Figure 31: A) α-Alkoxypentafluorosulfanylation (top) and selected examples from the substrate scope (bottom). ...
Figure 32: A) Oxidative amination of arenes with azoles catalyzed by N-Ph PTZ. B) Selected examples from the s...
Figure 33: A) C(sp3)–H bond activation by HAT via chloride oxidation by *N-Ph PTZ•+. B) Proposed mechanism for...
Figure 34: A) Recycling e-PRC C–H azolation of electron-rich arenes with pyrazoles using Mes-Acr+ as a photoca...
Figure 35: A) Radical ion e-PRC direct oxidation of unactivated arenes using TAC+ as an electro-activated phot...
Figure 36: A) Radical ion e-PRC direct oxidation of unactivated arenes using TPA as an electro-activated photo...
Figure 37: Proposed mechanism (top) and mode of preassembly (bottom).
Figure 38: A) Possible preassemblies of reactive (left) vs unreactive (right) arenes. B) Calculated spin densi...
Figure 39: A) Recycling e-PRC C(sp2 )–H acetoxylation of arenes using DDQ as a photocatalyst. B) Proposed cata...
Figure 40: Gram scale hydroxylation of benzene in a recirculated flow setup.
Figure 41: A) Radical ion e-PRC vicinal diamination of alkylarenes using TAC+ as an electro-activated photocat...
Figure 42: A) Sequential oxygenation of multiple adjacent C–H bonds under radical ion e-PRC using TAC+ as an e...
Figure 43: A) Enantioselective recycling e-PRC cyanation of benzylic C–H bonds using ADQS as photocatalyst. B)...
Figure 44: Proposed tandem mechanism by Xu and co-workers.
Figure 45: A) Enantioselective recycling e-PRC decarboxylative cyanation using Cu(acac)2, Ce(OTf)3 and a box l...
Figure 46: A) Enantioselective recycling e-PRC benzylic cyanation using Cu(MeCN)4BF4, box ligand and anthraqui...
Figure 47: A) Radical ion e-PRC acetoxyhydroxylation of aryl olefins using TAC+ as an electro-activated photoc...
Figure 48: Selected examples from the substrate scope.
Figure 49: Photoelectrochemical acetoxyhydroxylation in a recirculated flow setup.
Figure 50: A) Radical ion e-PRC aminooxygenation of aryl olefins using TAC+ as an electro-activated photocatal...
Figure 51: A) Recycling e-PRC C–H alkylation of heteroarenes with organic trifluoroborates using Mes-Acr+ as p...
Figure 52: A) Recycling e-PRC decarboxylative C–H alkylation of heteroarenes using CeCl3·7H2O as catalyst. B) ...
Figure 53: A) Recycling e-PRC decarboxylative C–H alkylation of heteroarenes using Fe(NH4)2(SO4)2·6H2O as cata...
Figure 54: A) Recycling e-PRC C–H alkylation of heteroarenes with alkyl oxalates and 4CzIPN as photocatalyst. ...
Figure 55: A) Recycling e-PRC decarboxylative C–H carbamoylation of heteroarenes using 4CzIPN as photocatalyst...
Figure 56: A) Photoelectrochemical HAT-mediated hydrocarbon activation via the chlorine radical. B) Proposed m...
Figure 57: A) Selected examples from the substrate scope. B) Gram and decagram scale semi-continuous flow PEC ...
Figure 58: A) Photoelectrochemical HAT-mediated dehydrogenative coupling of benzothiazoles with aliphatic C–H ...
Figure 59: A) Photoelectrochemical HAT activation of ethers using electro-activated TAC+ as photocatalyst. B) ...
Figure 60: Selected examples from the substrate scope.
Figure 61: A) Photoelectrochemical HAT-mediated synthesis of alkylated benzimidazo-fused isoquinolinones using...
Figure 62: A) Decoupled photoelectrochemical cerium-catalyzed oxydichlorination of alkynes using CeCl3 as cata...
Figure 63: Proposed decoupled photoelectrochemical mechanism.
Figure 64: A) Decoupled photoelectrochemical ring-opening bromination of tertiary cycloalkanols using MgBr2 as...
Figure 65: A) Recycling e-PRC ring-opening functionalization of cycloalkanols using CeCl3 as catalyst. B) Prop...
Figure 66: Selected examples from the substrate scope of the PEC ring-opening functionalization.
Figure 67: A) Radical ion e-PRC reduction of chloro- and bromoarenes using DCA as catalyst and various accepto...
Figure 68: A) Screening of different phthalimide derivatives as catalyst for the e-PRC reduction of aryl halid...
Figure 69: Screening of different organic catalysts for the e-PRC reduction of trialkylanilium salts.
Figure 70: A) e-PRC reduction of phosphonated phenols and anilinium salts. B) Selected examples from the subst...
Figure 71: A) ConPET and e-PRC reduction of 4-bromobenzonitrile using a naphthalene diimide (NDI) precatalyst ...
Figure 72: A) Radical ion e-PRC reduction of phosphinated aliphatic alcohols with n-BuO-NpMI as catalyst. B) C...
Figure 73: Selected examples from the substrate scope.
Figure 74: A) Recycling e-PRC reductive dimerization of benzylic chlorides using a [Cu2] catalyst. B) Proposed...
Figure 75: A) Decoupled photoelectrochemical C–H alkylation of heteroarenes through deamination of Katritzky s...
Figure 76: Proposed mechanism by Chen and co-workers.
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
- was related to enhancement of selective absorption, considering the use of a visible-light source. In 2019, Glorius and colleagues [11] proposed a method of employing an EDA complex formed by indole derivative 98 and the Katritzky salt 99 as well as morpholine as organic base to obtain alkylated
- indole derivatives 100 under blue-light irradiation (Scheme 35). Given the UV–vis spectra of the reaction mixture and its components, there was no evidence of the formation of a ternary EDA complex between Katritzky salt 99, 98, and morpholine. Moreover, the TDDFT calculation showed that electron
- yield of this reaction can reach 7.6 g ⋅ h−1 on a gram scale, indicating that the flow step is promising in photochemistry. In 2019, Aggarwal and colleagues [38] employed Katritzky salt 119 as electron acceptor and HE 79 as electron donor to form an EDA complex, providing the corresponding alkyl radical
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.
Photocatalytic deaminative benzylation and alkylation of tetrahydroisoquinolines with N-alkylpyrydinium salts
- David Schönbauer,
- Carlo Sambiagio,
- Timothy Noël and
- Michael Schnürch
Beilstein J. Org. Chem. 2020, 16, 809–817, doi:10.3762/bjoc.16.74
- (sp3) coupling; deaminative coupling; Katritzky salt; photoredox catalysis; Introduction The selective formation of new carbon–carbon bonds via direct C–H functionalization bears the potential of being a process of high efficiency [1][2][3]. Since C–H bonds are omnipresent in organic compounds it is
- benzylation of N-aryl-THIQs [47]: After excitation of the catalyst, the Katritzky salt is reduced via SET, giving a Ru(III) species and intermediate III, followed by C–N cleavage to give benzylic radical IV and triphenylpyridine [45]. The Ru(II) catalyst is regenerated by another SET from the THIQ derivative
Graphical Abstract
Scheme 1: Examples of photocatalytic C–C bond formation by nucleophilic trapping of a reactive THIQ intermedi...
Figure 1: Kinetic profile for the benzylation of 1 to 3.
Scheme 2: Benzylation of N-phenyl-THIQ.
Scheme 3: Benzylation of substituted N-arylTHIQs.
Scheme 4: Removal of the PMP protecting group.
Scheme 5: Alkylation of N-phenyl-THIQ derivatives. Conditions: a2 mol % [Ir(dtbbpy)(ppy)2]PF6, DMA, 60 h; b2 ...
Scheme 6: Proposed mechanism.
