Silica-immobilized chiral dirhodium(II) catalyst for enantioselective carbenoid reactions.

Org Lett

Department of Chemistry, Emory University , 1515 Dickey Drive, Atlanta, Georgia 30322, United States , and School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, 311 Ferst Drive, Atlanta, Georgia 30322, United States.

Published: December 2013

A silica-supported dirhodium(II) tetraprolinate catalyst was synthesized in four steps from l-proline and used in a range of enantioselective transformations of donor/acceptor carbenoids. These include cyclopropenation, cyclopropanation, tandem ylide formation/[2,3] sigmatropic rearrangement, and a variety of combined C-H functionalization/Cope rearrangement reactions. The products of these transformations were obtained in yields and levels of enantioselectivity comparable to those obtained with its homogeneous counterpart, Rh2(S-DOSP)4. The silica-supported Rh2(S-DOSP)4 derivative was successfully recycled over five reactions.

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http://dx.doi.org/10.1021/ol403006rDOI Listing

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