Enantioselective intramolecular cyclopropanation of α-diazo-β-keto sulfones: asymmetric synthesis of bicyclo[4.1.0]heptanes and tricyclo[4.4.0.0]decenes
作者:Masahiro Honma、Masahisa Nakada
DOI:10.1016/j.tetlet.2003.09.215
日期:2003.12
(IMCP) reaction of α-diazo-β-keto sulfones affording bicyclo[4.1.0]heptanes such as 9a–d is found to proceed with high enantioselectivity (93–98% ee). The yield is moderate due to the competing intramolecular C–Hinsertionreaction. As intramolecular C–Hinsertionreaction is not observed in the reaction of the substrates possessing a quaternary carbon at the allylic position, the reactions of 19a