作者:Katsukiyo Miura、Joji Hayashida、Tatsuyuki Takahashi、Hisashi Nishikori、Akira Hosomi
DOI:10.1016/s0022-328x(03)00533-3
日期:2003.11
In the presence of a catalytic amount of (TsOHH2O)-H-. or TiCl4, 5-silyl-4-pentenoic acids (1), namely vinylsilanes with a carboxy group, were smoothly cyclized to gamma-lactones in good to high yields. The difference in the geometry of the carbon-carbon double-bond did not affect the reaction rate. The TiCl4-catalyzed cyclization of the substrates bearing a phenyl or alkyl group at the homoallylic position showed moderate cis-selectivity, while introduction of a substituent into the allylic position led to high transselectivity. (C) 2003 Elsevier B.V. All rights reserved.