Enantioselective Addition of α-Nitroesters to Alkynes
Ryan T Davison1, Patrick D Parker1, Xintong Hou1
1Department of Chemistry, University of California, Irvine, Irvine, CA, 92697, USA.
Abstract:
By using Rh-H catalysis, we couple α-nitroesters and alkynes to prepare α-amino-acid precursors. This atom-economical strategy generates two contiguous stereocenters, with high enantio- and diastereocontrol. In this transformation, the alkyne undergoes isomerization to generate a RhIII -π-allyl electrophile, which is trapped by an α-nitroester nucleophile. A subsequent reduction with In powder transforms the allylic α-nitroesters to the corresponding α,α-disubstituted α-amino esters.
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