Search for "photochemical activation" in Full Text gives 9 result(s) in Beilstein Journal of Organic Chemistry.
Beilstein J. Org. Chem. 2024, 20, 787–814, doi:10.3762/bjoc.20.72
Graphical Abstract
Scheme 1: Classes of hydrochlorination reactions discussed in this review.
Figure 1: Mayr’s nucleophilicity parameters for several alkenes. References for each compound can be consulte...
Figure 2: Hydride affinities relating to the reactivity of the corresponding alkene towards hydrochlorination....
Scheme 2: Distinction of polar hydrochlorination reactions.
Scheme 3: Reactions of styrenes with HCl gas or HCl solutions.
Figure 3: Normal temperature dependence for the hydrochlorination of (Z)-but-2-ene.
Figure 4: Pentane slows down the hydrochlorination of 11.
Scheme 4: Recently reported hydrochlorinations of styrenes with HCl gas or HCl solutions.
Scheme 5: Hydrochlorination reactions with di- and trisubstituted alkenes.
Scheme 6: Hydrochlorination of fatty acids with liquified HCl.
Scheme 7: Hydrochlorination with HCl/DMPU solutions.
Scheme 8: Hydrochlorination with HCl generated from EtOH and AcCl.
Scheme 9: Hydrochlorination with HCl generated from H2O and TMSCl.
Scheme 10: Regioisomeric mixtures of chlorooctanes as a result of hydride shifts.
Scheme 11: Regioisomeric mixtures of products as a result of methyl shifts.
Scheme 12: Applications of the Kropp procedure on a preparative scale.
Scheme 13: Curious example of polar anti-Markovnikov hydrochlorination.
Scheme 14: Unexpected and expected hydrochlorinations with AlCl3.
Figure 5: Ex situ-generated HCl gas and in situ application for the hydrochlorination of activated alkenes (*...
Scheme 15: HCl generated by Grob fragmentation of 92.
Scheme 16: Formation of chlorophosphonium complex 104 and the reaction thereof with H2O.
Scheme 17: Snyder’s hydrochlorination with stoichiometric amounts of complex 104 or 108.
Scheme 18: In situ generation of HCl by mixing of MsOH with CaCl2.
Scheme 19: First hydrochlorination of alkenes using hydrochloric acid.
Scheme 20: Visible-light-promoted hydrochlorination.
Scheme 21: Silica gel-promoted hydrochlorination of alkenes with hydrochloric acid.
Scheme 22: Hydrochlorination with hydrochloric acid promoted by acetic acid or iron trichloride.
Figure 6: Metal hydride hydrogen atom transfer reactions vs cationic reactions; BDE (bond-dissociation energy...
Scheme 23: Carreira’s first report on radical hydrochlorinations of alkenes.
Figure 7: Mechanism for the cobalt hydride hydrogen atom transfer reaction reported by Carreira.
Scheme 24: Radical “hydrogenation” of alkenes; competing chlorination reactions.
Scheme 25: Bogers iron-catalyzed radical hydrochlorination.
Scheme 26: Hydrochlorination instead of hydrogenation product.
Scheme 27: Optimization of the Boger protocol by researchers from Merck [88,89].
Figure 8: Proposed mechanism for anti-Markovnikov hydrochlorination by Nicewicz.
Scheme 28: anti-Markovnikov hydrochlorinations as reported by Nicewicz.
Figure 9: Mechanism for anti-Markovnikov hydrochlorination according to Ritter.
Scheme 29: anti-Markovnikov hydrochlorinations as reported by Nicewicz; rr (regioisomeric ratio) corresponds t...
Scheme 30: anti-Markovnikov hydrochlorinations as reported by Liu.
Beilstein J. Org. Chem. 2020, 16, 2948–2953, doi:10.3762/bjoc.16.244
Graphical Abstract
Figure 1: (a) Cyclic voltammetry onto microelectrode arrays (Ø = 20 µm) in acetonitrile freshly distilled aft...
Figure 2: Variation of the current reduction (i2) of SF6 onto Pt macroelectrode (Ø = 0.76 mm) at −2.3 V vs Fc+...
Figure 3: Single compartment three-electrode experiment. 1: Balloon of SF6, 2: electrochemical cell, 3: refer...
Figure 4: Electrolysis of SF6 at −2.3 V vs Fc+/Fc in acetonitrile freshly distilled after addition of TBAClO4...
Figure 5: 19F NMR evolution of the crude mixture along the time after electrolysis realized at constant poten...
Beilstein J. Org. Chem. 2020, 16, 2484–2504, doi:10.3762/bjoc.16.202
Graphical Abstract
Figure 1: The momentum transport affects the mass transfer and the light field. All transport phenomena need ...
Figure 2: Common photomicroreactor designs: (a) Straight channel, (b) serpentine channel, (c) square serpenti...
Figure 3: Benchmarked photoreactors: (a) Microcapillaries in parallel, (b) microcapillaries in series, (c) fl...
Figure 4: Photochemical reactions that are detailed in Table 1.
Figure 5: Structured reactors designed for enhancing the mass transfer: (a) Packed bed photoreactor, (b) mono...
Figure 6: Comparison of the LED board designs of photomicroreactors: (a) CC array design, (b) MC array design...
Figure 7: Illustration of the light scattering phenomenon inside a photocatalytic flow reactor.
Figure 8: Efficiency of the absorption process in scattering situations with respect to pure absorption situa...
Figure 9: Different types of distributors: (a) Traditional or consecutive manifold, (b) bifurcation unit dist...
Beilstein J. Org. Chem. 2017, 13, 2764–2799, doi:10.3762/bjoc.13.272
Graphical Abstract
Scheme 1: Trifluoromethylation of enol acetates by Langlois.
Scheme 2: Trifluoromethylation of (het)aryl enol acetates.
Scheme 3: Mechanism for the trifluoromethylation of enol acetates.
Scheme 4: Oxidative trifluoromethylation of unactivated olefins and mechanistic pathway.
Scheme 5: Oxidative trifluoromethylation of acetylenic substrates.
Scheme 6: Metal free trifluoromethylation of styrenes.
Scheme 7: Synthesis of α-trifluoromethylated ketones by oxytrifluoromethylation of heteroatom-functionalised ...
Scheme 8: Catalysed photoredox trifluoromethylation of vinyl azides.
Scheme 9: Oxidative difunctionalisation of alkenyl MIDA boronates.
Scheme 10: Synthesis of β-trifluoromethyl ketones from cyclopropanols.
Scheme 11: Aryltrifluoromethylation of allylic alcohols.
Scheme 12: Cascade multicomponent synthesis of nitrogen heterocycles via azotrifluoromethylation of alkenes.
Scheme 13: Photocatalytic azotrifluoromethylation of alkenes with aryldiazonium salts and CF3SO2Na.
Scheme 14: Copper-promoted intramolecular aminotrifluoromethylation of alkenes with CF3SO2Na.
Scheme 15: Oxytrifluoromethylation of alkenes with CF3SO2Na and hydroxamic acid.
Scheme 16: Manganese-catalysed oxytrifluoromethylation of styrene derivatives.
Scheme 17: Oxytrifluoromethylation of alkenes with NMP/O2 and CF3SO2Na.
Scheme 18: Intramolecular oxytrifluoromethylation of alkenes.
Scheme 19: Hydrotrifluoromethylation of styrenyl alkenes and unactivated aliphatic alkenes.
Scheme 20: Hydrotrifluoromethylation of electron-deficient alkenes.
Scheme 21: Hydrotrifluoromethylation of alkenes by iridium photoredox catalysis.
Scheme 22: Iodo- and bromotrifluoromethylation of alkenes by CF3SO2Na/I2O5 or CF3SO2Na / NaBrO3.
Scheme 23: N-methyl-9-mesityl acridinium and visible-light-induced chloro-, bromo- and SCF3 trifluoromethylati...
Scheme 24: Carbotrifluoromethylation of N-arylacrylamides with CF3SO2Na / TBHP by Lipshutz.
Scheme 25: Carbotrifluoromethylation of N-arylacrylamides with CF3SO2Na/TBHP reported by Lei.
Scheme 26: Carbotrifluoromethylation of N-arylacrylamides with CF3SO2Na/(NH4)2S2O8.
Scheme 27: Metal-free carbotrifluoromethylation of N-arylacrylamides with CF3SO2Na/K2S2O8 reported by Wang.
Scheme 28: Metal-free carbotrifluoromethylation of N-arylacrylamides with CF3SO2Na/PIDA reported by Fu.
Scheme 29: Metal-free cascade trifluoromethylation/cyclisation of N-arylmethacrylamides (a) and enynes (b) wit...
Scheme 30: Trifluoromethylation/cyclisation of N-arylcinnamamides: Synthesis of 3,4-disubstituted dihydroquino...
Scheme 31: Trifluoromethylation/cyclisation of aromatic-containing unsaturated ketones.
Scheme 32: Chemo- and regioselective cascade trifluoromethylation/heteroaryl ipso-migration of unactivated alk...
Scheme 33: Copper-mediated 1,2-bis(trifluoromethylation) of alkenes.
Scheme 34: Trifluoromethylation of aromatics with CF3SO2Na reported by Langlois.
Scheme 35: Baran’s oxidative C–H trifluoromethylation of heterocycles.
Scheme 36: Trifluoromethylation of acetanilides and anilines.
Scheme 37: Trifluoromethylation of heterocycles in water.
Scheme 38: Trifluoromethylation of coumarins in a continuous-flow reactor.
Scheme 39: Oxidative trifluoromethylation of coumarins, quinolines and pyrimidinones.
Scheme 40: Oxidative trifluoromethylation of pyrimidinones and pyridinones.
Scheme 41: Phosphovanadomolybdic acid-catalysed direct C−H trifluoromethylation.
Scheme 42: Oxidative trifluoromethylation of imidazopyridines and imidazoheterocycles.
Scheme 43: Oxidative trifluoromethylation of imidazoheterocycles and imidazoles in ionic liquid/water.
Scheme 44: Oxidative trifluoromethylation of 8-aminoquinolines.
Scheme 45: Oxidative trifluoromethylation of various 8-aminoquinolines using the supported catalyst CS@Cu(OAc)2...
Scheme 46: Oxidative trifluoromethylation of the naphthylamide 70.
Scheme 47: Oxidative trifluoromethylation of various arenes in the presence of CF3SO2Na and sodium persulfate.
Scheme 48: Trifluoromethylation of electron-rich arenes and unsymmetrical biaryls with CF3SO2Na in the presenc...
Figure 1: Trifluoromethylated coumarin and flavone.
Scheme 49: Metal-free trifluoromethylation catalysed by a photoredox organocatalyst.
Scheme 50: Quinone-mediated trifluoromethylation of arenes and heteroarenes.
Scheme 51: Metal- and oxidant-free photochemical trifluoromethylation of arenes.
Scheme 52: Copper-mediated trifluoromethylation of arenediazonium tetrafluoroborates.
Scheme 53: Oxidative trifluoromethylation of aryl- and heteroarylboronic acids.
Scheme 54: Oxidative trifluoromethylation of aryl- and vinylboronic acids.
Scheme 55: Oxidative trifluoromethylation of unsaturated potassium organotrifluoroborates.
Scheme 56: Oxidative trifluoromethylation of (hetero)aryl- and vinyltrifluoroborates.
Scheme 57: Copper−catalysed decarboxylative trifluoromethylation of cinnamic acids.
Scheme 58: Iron-mediated decarboxylative trifluoromethylation of α,β-unsaturated carboxylic acids.
Scheme 59: Cu/Ag-catalysed decarboxylative trifluoromethylation of cinnamic acids.
Scheme 60: I2O5-Promoted decarboxylative trifluoromethylation of cinnamic acids.
Scheme 61: Silver(I)-catalysed denitrative trifluoromethylation of β-nitrostyrenes.
Scheme 62: Copper-catalysed direct trifluoromethylation of styrene derivatives.
Scheme 63: Transition-metal-free synthesis of β-trifluoromethylated enamines.
Scheme 64: I2O5-mediated iodotrifluoromethylation of alkynes.
Scheme 65: Silver-catalysed tandem trifluoromethylation/cyclisation of aryl isonitriles.
Scheme 66: Photoredox trifluoromethylation of 2-isocyanobiphenyls.
Scheme 67: Trifluoromethylation of potassium alkynyltrifluoroborates with CF3SO2Na.
Scheme 68: N-trifluoromethylation of nitrosoarenes with CF3SO2Na (SQ: semiquinone).
Scheme 69: Trifluoromethylation of disulfides with CF3SO2Na.
Scheme 70: Trifluoromethylation of thiols with CF3SO2Na/I2O5.
Scheme 71: Electrophilic trifluoromethylsulfenylation by means of CF3SO2Na/(EtO)2P(O)H/CuCl/DMSO.
Scheme 72: Electrophilic trifluoromethylsulfenylation by means of CF3SO2Na/(EtO)2P(O)H/TMSCl.
Scheme 73: Electrophilic trifluoromethylsulfenylation by means of CF3SO2Na/PPh3/N-chlorophthalimide.
Scheme 74: Electrophilic trifluoromethylsulfenylation by means of CF3SO2Na/PCl3.
Scheme 75: Electrophilic trifluoromethylsulfenylation by means of CF3SO2Na/PCl3.
Scheme 76: Trifluoromethylsulfenylation of aryl iodides with in situ generated CuSCF3 (DMI: 1,3-dimethyl-2-imi...
Scheme 77: Pioneering trifluoromethylsulfinylation of N, O, and C-nucleophiles.
Scheme 78: Trifluoromethylsulfinylation of (1R,2S)-ephedrine (Im: imidazole; DIEA: N,N-diisopropylethylamine).
Scheme 79: Trifluoromethylsulfinylation of substituted benzenes with CF3SO2Na/CF3SO3H.
Scheme 80: Trifluoromethylsulfinylation of indoles with CF3SO2Na/P(O)Cl3.
Scheme 81: Trifluoromethylsulfinylation of indoles with CF3SO2Na/PCl3.
Scheme 82: Formation of triflones from benzyl bromides (DMA: dimethylacetamide).
Scheme 83: Formation of α-trifluoromethylsulfonyl ketones, esters, and amides.
Scheme 84: Allylic trifluoromethanesulfonylation of aromatic allylic alcohols.
Scheme 85: Copper-catalysed couplings of aryl iodonium salts with CF3SO2Na.
Scheme 86: Palladium-catalysed trifluoromethanesulfonylation of aryl triflates and chlorides with CF3SO2Na.
Scheme 87: Copper-catalysed coupling of arenediazonium tetrafluoroborates with CF3SO2Na.
Scheme 88: Synthesis of phenyltriflone via coupling of benzyne with CF3SO2Na.
Scheme 89: Synthesis of 1-trifluoromethanesulfonylcyclopentenes from 1-alkynyl-λ3-bromanes and CF3SO2Na.
Scheme 90: One-pot synthesis of functionalised vinyl triflones.
Scheme 91: Regioselective synthesis of vinyltriflones from styrenes.
Scheme 92: Trifluoromethanesulfonylation of alkynyl(phenyl) iodonium tosylates by CF3SO2Na.
Scheme 93: Synthesis of thio- and selenotrifluoromethanesulfonates.
Beilstein J. Org. Chem. 2017, 13, 33–42, doi:10.3762/bjoc.13.5
Graphical Abstract
Figure 1: Menthol auxiliaries 1–4 used in the following anodic coupling reactions.
Scheme 1: Synthesis of carboxylic acids 13a/b–18a/b.
Scheme 2: (a) Preparation of benzyl 2-isopropylmalonate (5) and (b) preparation of benzyl 2-tert-butylmalonat...
Scheme 3: Coelectrolysis (hetero-coupling) of carboxylic acids 13–17 with 3,3-dimethylbutyric acid (20).
Figure 2: Crystal structure of the minor diastereomer 23b.
Figure 3: Cyclic voltammograms of the malonic derivatives 15a/b, 16a/b and 18a/b (scan rate: 500 mA/s, solven...
Scheme 4: Homo-coupling of carboxylic acids 13a/b–16a/b to diesters 26a/b/c–29a/b/c (n.d.: not determined).
Figure 4: Crystal structure of major diastereomer 28a.
Figure 5: Crystal structure of major diastereomer 29a.
Figure 6: Discrimination of diastereomeric faces in the menthol substituted radical A and in the 8-phenylment...
Scheme 5: Reductive cleavage of 30a–c to 8-phenylmenthol (3) and 31a–c.
Beilstein J. Org. Chem. 2016, 12, 1322–1333, doi:10.3762/bjoc.12.125
Graphical Abstract
Scheme 1: Imine formation and isomerization reactions from NH carbene complexes Cr(CO)5(E-2) (a) [27], Cr(CO)5(E/Z...
Scheme 2: Synthesis of W(CO)5(E-2) from W(CO)5(1Et) [20,21] and aminoferrocene [40,41] with concomitant formation of E-1,2-...
Scheme 3: Reaction pathways 1a/1b (migration–elimination) and 2a/2b (elimination–migration) for the formation...
Scheme 4: Reaction pathways 3a/3b/3c (CO dissociation) for the formation of imine E-3 from W(CO)5(E-2).
Figure 1: DFT calculated oxidative addition/pseudorotation/reductive elimination pathway 3c from W(CO)4(E-2) ...
Figure 2: DFT calculated geometries of the two hydrido intermediates cis(N,H)-W(CO)4(H)(Z-15) and cis(C,H)-W(...
Scheme 5: Proposed reaction sequence from W(CO)5(E-2) to W(CO)5(PPh3) in the presence of triphenylphosphane.
Beilstein J. Org. Chem. 2013, 9, 1745–1750, doi:10.3762/bjoc.9.201
Graphical Abstract
Scheme 1: Formation of azirines 2 from vinyl azides 1, photoinduced ring-opening to the nitrile ylides 3, and...
Scheme 2: Solid-phase assisted synthesis of vinyl azides 1 from alkenes 6 under flow conditions [9].
Scheme 3: Schematic presentation of the flow set-up for the synthesis of 2H-azirines 2 under inductive heatin...
Scheme 4: Photoinduced cycloadditions of vinyl azides 1a–f and electron-deficient alkenes 4a–d. All experimen...
Scheme 5: Photoinduced cycloaddtion of vinyl azide 1c and diisopropyl azodicarboxylate (4e). The experiment w...
Scheme 6: Photoinduced cycloaddtion of vinyl azide 1b and alkyne 4f. The experiment was conducted at room tem...
Scheme 7: Formation of 2,5-dihydrooxazole 9 starting from vinyl azide 1g under flow conditions (c = 0.01 M, f...
Beilstein J. Org. Chem. 2013, 9, 1607–1612, doi:10.3762/bjoc.9.183
Graphical Abstract
Figure 1: UV–vis absorption spectra of organotellurium chain transfer agent 1 and dimethyl ditelluride in tol...
Scheme 1: Photopolymerization in the presence of organotellurium chain transfer agent 1.
Figure 2: GPC traces for the polymerizations of MMA (Table 1). The percentages in the legend refer to the ND filters...
Scheme 2: Activation and deactivation mechanism of dormant (P-TeMe) and ditelluride.
Figure 3: Experimental setup for the photopolymerization using the LED.
Beilstein J. Org. Chem. 2013, 9, 800–808, doi:10.3762/bjoc.9.91
Graphical Abstract
Scheme 1: Photoinduced electron transfer as an access to radical chemistry.
Figure 1: Reduction potential (versus SCE) of the ground and excited state of acceptors and oxidation potenti...
Figure 2: UV-monitoring of: (a) a 2 × 10−4 M solution of TCB in the presence of Bu4Sn (10−2 M) and (b) a 1.5 ...
Figure 3: Absorption spectra of a freeze–pump–thaw deoxygenated MeCN solution irradiated at 313 nm of (a) 1,2...
Scheme 2: Mechanistic scheme.
Figure 4: Thermodynamics of the redox processes discussed (solid arrows represent exergonic electron donation...