Tungsten-Catalyzed Regioselective and Stereospecific Ring Opening of 2,3-Epoxy Alcohols and 2,3-Epoxy Sulfonamides
摘要:
The first catalytic, highly C3-selective, stereosepecific ring-opening reaction of 2,3-epoxy alcohols and 2,3-epoxy sulfonamides has been accomplished. This process was efficiently promoted by W-salts, and the developed method was applicable to various epoxides with diverse N- and O-nucleophiles affording the products in good to excellent yields (up to 95%) and generally with high regioselectivities (C3:C2 up to >99:1).
Hf(IV)-Catalyzed Enantioselective Epoxidation of <i>N</i>-Alkenyl Sulfonamides and <i>N</i>-Tosyl Imines
作者:José Luis Olivares-Romero、Zhi Li、Hisashi Yamamoto
DOI:10.1021/ja211880s
日期:2012.3.28
Asymmetric epoxidation of allylic and homoallylic amine derivatives catalyzed by Hf(IV)-bishydroxamic acid complexes is described. Under similar conditions, aldimine and ketimine produced oxaziridines. The sulfonyl group is demonstrated to be an effective directing group for these transformations.
Tungsten-Catalyzed Regioselective and Stereospecific Ring Opening of 2,3-Epoxy Alcohols and 2,3-Epoxy Sulfonamides
作者:Chuan Wang、Hisashi Yamamoto
DOI:10.1021/ja5029809
日期:2014.5.14
The first catalytic, highly C3-selective, stereosepecific ring-opening reaction of 2,3-epoxy alcohols and 2,3-epoxy sulfonamides has been accomplished. This process was efficiently promoted by W-salts, and the developed method was applicable to various epoxides with diverse N- and O-nucleophiles affording the products in good to excellent yields (up to 95%) and generally with high regioselectivities (C3:C2 up to >99:1).
Catalyst-controlled site-selective asymmetric epoxidation of nerylamine and geranylamine derivatives
作者:Tomoya Nobuta、Takeo Kawabata
DOI:10.1039/c7cc04809b
日期:——
Novel catalysts for site- and enantioselective epoxidation of nerylamine and geranylamine derivatives have been developed. Although mCPBA oxidation took place selectively at the more electron-rich double bond to give the 6,7-epoxides, these catalysts provide the 2,3-epoxides in moderate to high enantioselectivity via the oxidation of the relatively electron-deficient double bond.