ChemInform Abstract: Catalytic Asymmetric Synthesis of 2,2-Disubstituted Terminal Epoxides via Dimethyloxosulfonium Methylide Addition to Ketones

Autor: Toshihiko Sone, Akitake Yamaguchi, Masakatsu Shibasaki, Shigeki Matsunaga
Rok vydání: 2008
Předmět:
Zdroj: ChemInform. 39
ISSN: 1522-2667
0931-7597
DOI: 10.1002/chin.200849095
Popis: Catalytic asymmetric Corey−Chaykovsky epoxidation of ketones with dimethyloxosulfonium methylide 2 using an LLB 1a + Ar3P═O complex proceeded smoothly at room temperature, and 2,2-disubstituted terminal epoxides were obtained in high enantioselectivity (91−97%) and yield (>88−99%) from a broad range of methyl ketones with 1−5 mol % catalyst loading. The use of achiral additive Ar3P═O 5i was important to achieve high enantioselectivity.
Databáze: OpenAIRE