New catalysts for the base-promoted isomerization of epoxides to allylic alcohols. Broadened scope and near-perfect asymmetric induction |
| |
Authors: | Bertilsson Sophie K Södergren Mikael J Andersson Pher G |
| |
Institution: | Department of Organic Chemistry, Institute of Chemistry, Uppsala University, Box 531, S-751 21 Uppsala, Sweden. |
| |
Abstract: | Optically active (1S,3R,4R)-3-N-(trans-2,5-dialkyl)pyrrolidinyl]methyl-2-azabicyclo-2.2.1]heptanes were evaluated as catalysts for the enantioselective beta-elimination of meso-epoxides. The (2R,5R)-dimethylpyrrolidinyl-substituted catalyst 4 exhibited exceptionally high enantioselectivity and reactivity, and several substrates were rearranged with enantioselectivities of 98-99% ee. In addition, the use of 4 allowed the first successful, true catalytic rearrangement of the difficult substrates cyclopentene oxide (81%, 96% ee) and (Z)-4-octene oxide (80%, 91% ee). |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|