Shortcut Approach to Cyclopenta[b]indoles by [3+2] Cyclodimerization of Indole-Derived Cyclopropanes

摘要

A new straightforward approach to 3-indolyl-derived cyclopenta[b]indoles by a Lewis acid triggered [3+2] cyclodimerization of 2-(3-indolyl)cyclopropane-l,l-dicarboxylic acid diesters was developed. This reaction exhibits exceptional chemo-, regio-, and diastereoselectivities, leading to the formation of an individual diastereomer with a relative configuration that corresponds to that of naturally occurring indole terpenoids.