Synthesis of Cyclobutenes by Highly Selective Transition‐Metal‐Catalyzed Ring Expansion of Cyclopropanes

Abstract

A highly chemoselective, regioselective, and stereospecific synthesis of polysubstituted cyclobutenes, by catalyst-controlled ring expansion of cyclopropanes via metal carbene intermediates, is reported. Transition-metal catalysts showed profound effects on the reactivity and selectivity of metal carbene intermediates in this ring-expansion reaction. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.