保护基团的邻基参与对1,3,5-三酮脱水环化反应的速率加速作用。

Rate-accelerating effect by the neighboring-group participation of protecting groups in the dehydrative cyclization of 1,3,5-triketones.

作者信息

Sakakura Akira, Watanabe Hitoshi, Ishihara Kazuaki

机构信息

Graduate School of Engineering, Nagoya University, Chikusa, Nagoya, Japan.

出版信息

Org Lett. 2008 Jun 19;10(12):2569-72. doi: 10.1021/ol800860p. Epub 2008 May 27.

DOI:10.1021/ol800860p

PMID:18503276

Abstract

Neighboring-group participation of an acyl protecting group efficiently promotes the Brønsted acid-catalyzed dehydrative cyclization of 1,3,5-triketones to gamma-pyrones, whereas a bulky silyloxy group in the beta-position retards the cyclization. This reaction provides an efficient synthetic route for a common intermediate for the synthesis of gamma-pyrone-containing bioactive natural products.

摘要

酰基保护基团的邻基参与有效地促进了布朗斯特酸催化的1,3,5-三酮脱水环化生成γ-吡喃酮，而β位上的大体积硅氧基则会阻碍环化反应。该反应为合成含γ-吡喃酮的生物活性天然产物的常见中间体提供了一条有效的合成路线。