Acceptor/Acceptor‐Substituted Diazo Reagents for Carbene Transfers: Cobalt‐Catalyzed Asymmetric <i>Z‐</i>Cyclopropanation of Alkenes with α‐Nitrodiazoacetates

Abstract

Surprisingly cis-tematic! The cobalt(II) complex of a D2-symmetric chiral porphyrin is an effective catalyst for asymmetric cyclopropanation with α-nitrodiazoacetates (see scheme). The catalytic system is general and suitable for electron-sufficient, -neutral, and -deficient alkenes, forming the corresponding cyclopropane nitroesters in high yields. In addition to high diastereo- and enantioselectivity, the catalytic process exhibits atypical Z selectivity. 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.