Generation and intramolecular cyclization of α-phenylsulfenyl and α-alkylsulfenyl radicals
摘要:
alpha-Phenylsulfenyl radicals are generated by the reaction of diphenyl dithioacetals or phenyl alpha-chlorosulfides with tributyltin hydride. Alkyl phenyl dithioacetals react selectively with tributyltin hydride to give alpha-alkylsulfenyl radicals. 5-Exo-type of intramolecular cyclizations of these radicals are studied. The cyclization is most successful when the olefin is terminally substituted with an ester group. The cis/trans ratio of the cyclized product varies according to the reaction rates. With a faster cyclization, cis-isomer is the major product. A slower cyclization gives more trans-product. (C) 1997 Elsevier Science Ltd.
Generation and intramolecular cyclization of α-phenylsulfenyl and α-alkylsulfenyl radicals
摘要:
alpha-Phenylsulfenyl radicals are generated by the reaction of diphenyl dithioacetals or phenyl alpha-chlorosulfides with tributyltin hydride. Alkyl phenyl dithioacetals react selectively with tributyltin hydride to give alpha-alkylsulfenyl radicals. 5-Exo-type of intramolecular cyclizations of these radicals are studied. The cyclization is most successful when the olefin is terminally substituted with an ester group. The cis/trans ratio of the cyclized product varies according to the reaction rates. With a faster cyclization, cis-isomer is the major product. A slower cyclization gives more trans-product. (C) 1997 Elsevier Science Ltd.
Generation and intramolecular cyclization of α-phenylsulfenyl and α-alkylsulfenyl radicals
作者:Yeun-Min Tsai、Fu-Chang Chang、Jimin Huang、Chi-Lung Shiu、Chai-Lin Kao、Jyh-Shiunn Liu
DOI:10.1016/s0040-4020(97)00156-7
日期:1997.3
alpha-Phenylsulfenyl radicals are generated by the reaction of diphenyl dithioacetals or phenyl alpha-chlorosulfides with tributyltin hydride. Alkyl phenyl dithioacetals react selectively with tributyltin hydride to give alpha-alkylsulfenyl radicals. 5-Exo-type of intramolecular cyclizations of these radicals are studied. The cyclization is most successful when the olefin is terminally substituted with an ester group. The cis/trans ratio of the cyclized product varies according to the reaction rates. With a faster cyclization, cis-isomer is the major product. A slower cyclization gives more trans-product. (C) 1997 Elsevier Science Ltd.