Asymmetric Cyclopropanation of Olefins Catalyzed by a Chiral Cobalt(II) Porphyrin
Albrecht Berkessel, Erkan Ertürk and Jörg M. Neudörfl
Department für Chemie, Universität zu Köln, Greinstrasse 4, 50939 Köln, Germany
Abstract: The cobalt(II) complex of the Halterman porphyrin, 5,10,15,20-tetrakis[(1S,4R,5R,8S)-1,2,3,4,5,6,7,8-octahydro-1,4:5,8-dimethanoanthracene-9-yl]porphyrinato cobalt(II) [Co(por*)], was synthesized and its structure was identified by X-ray analysis. Up to 80:20 trans:cis diastereomeric ratio and 82% ee were achieved in the cyclopropanation of styrene with ethyl diazoacetate by using this cobalt(II) porphyrin complex as catalyst.Keywords : Asymmetric catalysis, cyclopropanation, cobalt, porphyrin, ethyl diazoacetate. © 2017 ACG Publications. All rights reserved.