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• 73188-49-5 2-phenyl-2-(phenylthio)propanal 
• 673-32-5 1-Phenylprop-1-yne 
• 882-33-7 diphenyldisulfane 
• 10243-15-9 3-bromo-2-methylbenzo[b]thiophene 
• 1801-99-6 2-mercaptobenzophenone 
• 108-98-5 thiophenol 
• 100-47-0 benzonitrile 
• 19614-16-5 2-bromo-1-(methylsulfanyl)benzene 
• 5698-59-9 benzo[c]thiophene-1,3-dione 
• 476653-35-7 {2-[1-(benzotriazol-1-yl)ethylsulfanyl]phenyl}(phenyl)methanone 
• 106236-66-2 1-methyl-2-phenyl-2-<(o-phenylthio)phenyl>vinyl bromide 
• 70132-76-2 3-phenyl-1,2-benzoisothiazole 
• 14273-06-4 1-ethoxy-1-propyne 

Relevant academic research and scientific papers

The energy-transfer-enabled biocompatible disulfide–ene reaction

Sulfur-containing molecules participate in many essential biological processes. Of utmost importance is the methylthioether moiety, present in the proteinogenic amino acid methionine and installed in tRNA by radical-S-adenosylmethionine methylthiotransferases. Although the thiol–ene reaction for carbon–sulfur bond formation has found widespread applications in materials or medicinal science, a biocompatible chemo- and regioselective hydrothiolation of unactivated alkenes and alkynes remains elusive. Here, we describe the design of a general chemoselective anti-Markovnikov hydroalkyl/aryl thiolation of alkenes and alkynes—also allowing the biologically important hydromethylthiolation—by triplet–triplet energy transfer activation of disulfides. This fast disulfide–ene reaction shows extraordinary functional group tolerance and biocompatibility. Transient absorption spectroscopy was used to study the sensitization process in detail. The hereby gained mechanistic insights were successfully employed for optimization of the catalytic system. This photosensitized transformation should stimulate bioimaging applications and carbon–sulfur bond-forming late-stage functionalization chemistry, especially in the context of metabolic labelling.

Palladium-Catalyzed Synthesis of 2,3-Disubstituted Benzothiophenes via the Annulation of Aryl Sulfides with Alkynes

A new method has been developed for the synthesis of 2,3-disubstituted benzothiophenes involving the palladium-catalyzed annulation of aryl sulfides with alkynes. This convergent approach exhibited good functional group tolerance, providing rapid access to a diverse array of derivatives from simple, readily available starting materials. This protocol can also be used to synthesize 2-silyl-substituted benzothiophenes, which can be used as versatile platforms for the synthesis of 2,3-unsymmetrically substituted benzothiophenes.

Nickel-catalyzed cycloadditions of thiophthalic anhydrideswith alkynes

Nickel-catalyzed cycloadditions have been developed where thiophthalic anhydrides reactwith alkynes to afford substituted sulfur-containing heterocyclic compounds. Selective formations of thioisocoumarins, benzothiophenes, and thiochromoneswre accomplishe

5,6,7,12-Tetrahydrodibenz[c,f][1,5]azabismocines: Highly reactive and recoverable organo-bismuth reagents for cross-coupling reactions with Aryl Bromides

Hypervalent organobismuth compounds efficiently couple with aryl bromides in the presence of [Pd(PPh3)4] catalyst. Application of this protocol to a one-pot multi-coupling reaction with bromophenylboronic esters leads to the formation of up to nine bonds in good yields (see scheme).

Novel syntheses of 2,3-disubstituted benzothiophenes

The sodium salts of o-sulfanylphenyl ketones 3a-g were treated with α-benzotriazol-1-ylalkyl chlorides 4a,b to give intermediates 5a-k in good yields. Compounds 5a-k, on treatment successively with LDA and Ti (0), gave benzothiophenes 7a-k.

Novel phenyl migration of 1-phenylbenzo[b]thiophenium triflates in the thermolysis

Thermolysis of 1-phenylbenzo[b]thiophenium triflates at 180°C causes phenyl migration to give 2-phenylbenzo[b]thiophenes in high yields. Interestingly, the thermolysis of 1-phenylbenzo[b]thiophenium triflates having a substituent at the 2 position affords

Reaction of Diphenyl Disulfide with Alkynes Promoted by Di-tert-butyl and Dibenzoyl Peroxides: a Useful Syntheic Route to 3- (and 2,3) Substituted Benzothiophenes

Thermal reactions of diphenyl disulfide 1 with phenylacetylenes 2a-e promoted by di-tert-butyl peroxide (TBP) at 110 or 150 deg C provides a useful synthetic route to the (2-substituted) 3-phenylbenzothiophenes 4a-e, which result from intramolecular cyclization of 1-phenyl-2-(phenylthio)vinyl radical intermediates 3a-e.Similar reactions of the disulfide 1 with tert-butyl- and trimethylsilylacetylenes 2f and 2g also provide the corresponding benzothiophenes 4f and 4g in satisfactory yields; low yields of the benzothiophene products 4h, i, however, are obtained with hex-1-yne 1h and hex-3-yne 1i.Evidence is presented that the thermal reaction of the disulfide 1 with the alkynes 2 at 100 deg C in the presence of dibenzoyl peroxide, while being of little use for the synthesis of benzothiophenes 4, generally leads to the 2-(phenylthio)vinyl benzoates 10; this is ascribed to initial addition of benzoyloxy radicals to alkyne triple bonds.

Free-Radical Reactions of Benzenethiol and Diphenyl Disulphide with Alkynes. Chemical Reactivity of Intermediate 2-(Phenylthio)vinyl Radicals

Reaction of benzenethiol at 100 deg C with neat alkyl- and dialkyl-acetylenes leads to virtually quantitative formation of isomeric mixtures of (E)- and (Z)-vinyl sulphide adducts in ratios which depend largely upon both the extent and the nature of alkyl substitution.Results are explained in terms of rapidly interconverting sp2-hybridized (E)- and (Z)-1-alkyl-2-(phenylthio)vinyl radical intermediates which can undergo hydrogen transfer from benzenethiol to an extent which is essentially dependent upon the steric hindrance of their cis-2-substituent.Consistent results are provided by related radical reactions of diphenyl disulphide with alkyl-substituted alkynes to afford varying amounts of 1,2-bis(phenylthio)ethylene adducts ascribable to SH2 reaction of the resulting 1-alkyl-2-(phenylthio)vinyl radicals with the disulphide present.Under analogous conditions benzenethiol and diphenyl disulphide react with phenylacetylenes to give vinyl sulphide or bissulphide adducts in a trans-stereoselective fashio.The findings are interpreted by suggesting, for the intermediate sp-hybridized 1-phenyl-2-(phenylthio)vinyl radicals, the occurrence of significant bonding interaction between the unpaired electron and the adjacent sulphur, which would essentially prevent attack of radical scavenger on the side cis to PhS.Evidence is also presented that 1-phenyl-2-(phenylthio)vinyl radicals can exhibit homolytic intramolecular cyclization reactions, leading to benzothiophene products to a comparatively much greater extent than the 1-alkyl-2-substituted analogues; however, 1-tert-butyl-2-(phenylthio)vinyl radical would represent a special case.

Photolysis of β-(o-Methylthiophenyl)vinyl Bromides. A Versatile Synthesis of Benzothiophens

Exclusive cyclization in photolysis of β-(o-methylthiophenyl)vinyl bromides to give benzothiophens is described.

EXCLUSIVE CYCLIZATION AT SULFUR IN PHOTOLYSIS OF β-VINYL BROMIDES

Photolysis of β-vinyl bromides, in contrast to the oxy-derivatives, resulted in exclusive cyclization at sulfur to give 1-benzothiophenes.The results were discussed by the nature of sulfur.