Guide to Enantioselective Dirhodium(II)-Catalyzed Cyclopropanation with Aryldiazoacetates

• Type of Material: Article
• Authors: Kathryn M. Chepiga, Emory University; Changming Qin, Emory University; Joshua S. Alford, Emory University; Spandan Chennamadhavuni, Emory University; Timothy M. Gregg, Canisius College; Jeremy P. Olson, Emory University; Huw Davies, Emory University
• Language: English
• Date: 2013-07-08
• Publisher: Elsevier
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: ©2013 Elsevier Ltd. All rights reserved.
• License: Creative Commons Attribution-NonCommerical-NoDerivs 3.0 Unported
• Final Published Version (URL): http://dx.doi.org/10.1016/j.tet.2013.04.075
• Title of Journal or Parent Work: Tetrahedron
• ISSN: 0040-4020
• Volume: 69
• Issue: 27-28
• Grant/Funding Information: This work was supported by the National Institutes of Health (DA023224).
• Keywords: Cyclopropanes; Asymmetric cyclopropanation; Donor/acceptor carbenoids; Phenyldiazoacetate; Dirhodium catalysis
• Research Categories: Chemistry, Biochemistry

Abstract

Catalytic enantioselective methods for the generation of cyclopropanes has been of longstanding pharmaceutical interest. Chiral dirhodium(II) catalysts prove to be an effective means for the generation of diverse cyclopropane libraries. Rh2(R-DOSP)4 is generaally the most effective catalyst for asymmetric intermolecular cyclopropanation of methyl aryldiazoacetates with styrene. Rh2(S-PTAD)4 provides high levels of enantioinduction with ortho-substituted aryldiazoacetates. The less-established Rh2(R-BNP)4 plays a complementary role to Rh2(R-DOSP)4 and Rh2(S-PTAD)4 in catalyzing highly enantioselective cyclopropanation of 3- methoxy-substituted aryldiazoacetates. Substitution on the styrene has only moderate influence on the asymmetric induction of the cyclopropanation.