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Enantio- and Diastereoselective 1,2-Additions to ?-Ketoesters with Diborylmethane and Substituted 1,1-Diborylalkanes.

ABSTRACT: The catalytic enantioselective synthesis of boronate-substituted tertiary alcohols through additions of diborylmethane and substituted 1,1-diborylalkanes to ?-ketoesters is reported. The reactions are catalyzed by readily available chiral phosphine/copper(I) complexes and produce ?-hydroxyboronates containing up to two contiguous stereogenic centers in up to 99:1 e.r. and greater than 20:1 d.r. The utility of the organoboron products is demonstrated through several chemoselective functionalizations. Evidence indicates the reactions occur via an enantioenriched ?-boryl-copper-alkyl intermediate.

SUBMITTER: Murray SA

PROVIDER: S-EPMC5000392 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Enantio- and Diastereoselective 1,2-Additions to α-Ketoesters with Diborylmethane and Substituted 1,1-Diborylalkanes.

Murray Stephanie A SA Green Jacob C JC Tailor Sanita B SB Meek Simon J SJ

Angewandte Chemie (International ed. in English) 20160620 31

The catalytic enantioselective synthesis of boronate-substituted tertiary alcohols through additions of diborylmethane and substituted 1,1-diborylalkanes to α-ketoesters is reported. The reactions are catalyzed by readily available chiral phosphine/copper(I) complexes and produce β-hydroxyboronates containing up to two contiguous stereogenic centers in up to 99:1 e.r. and greater than 20:1 d.r. The utility of the organoboron products is demonstrated through several chemoselective functionalizati ...[more]

PMID: 27321039

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