Pd -Catalyzed Enantioselective C(sp )-H Activation/Cross-Coupling Reactions of Free Carboxylic Acids.

Angew Chem Int Ed Engl

Department of Chemistry, The Scripps Research Institute (TSRI), 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA.

Published: February 2019

Pd -catalyzed enantioselective C(sp )-H cross-coupling of free carboxylic acids with organoborons has been realized using either mono-protected amino acid (MPAA) ligands or mono-protected aminoethyl amine (MPAAM) ligands. A diverse range of aryl- and vinyl-boron reagents can be used as coupling partners to provide chiral carboxylic acids. This reaction provides an alternative approach to the enantioselective synthesis of cyclopropanecarboxylic acids and cyclobutanecarboxylic acids containing α-chiral tertiary and quaternary stereocenters. The utility of this reaction was further demonstrated by converting the carboxylic acid into cyclopropyl amine without loss of optical activity.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6641982PMC
http://dx.doi.org/10.1002/anie.201813055DOI Listing

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