Asymmetric Propargylation of Ketones Using Allenylboronates Catalyzed by Chiral Biphenols
David S. Barnett and Scott E. Schaus*
*Department of Chemistry, Life Science and Engineering Building, Boston University, 24 Cummington Street, Boston, Massachusetts 02215, United States, Email: seschausbu.edu
D. S. Barnett, S. E. Schaus, Org. Lett., 2011, 13, 4020-4023.
DOI: 10.1021/ol201535b (free Supporting Information)
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3,3′-Br2-BINOL catalyze the enantioselective asymmetric propargylation of ketones using allenyldioxoborolane as nucleophile, in the absence of solvent, and under microwave irradiation to afford homopropargylic alcohols in good yields and high enantiomeric ratios. Diastereoselective propargylations using chiral racemic allenylboronates result in good diastereoselectivities.
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