Enantioselective Addition of α-Nitroesters to Alkynes

By using Rh-H catalysis, we couple alpha-nitroesters and alkynes to prepare alpha-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 Rh-III-pi-allyl electrophile, which is trapped by an alpha-nitroester nucleophile. A subsequent reduction with In powder transforms the allylic alpha-nitroesters to the corresponding alpha,alpha-disubstituted alpha-amino esters.

Automated summary

In this study, the coupling of alpha-nitroesters and alkynes using Rh-H catalysis was employed to prepare alpha-amino-acid precursors. This atom-economical strategy allows for the generation of two contiguous stereocenters with high enantio- and diastereocontrol. The alkyne undergoes isomerization to form a Rh-III-pi-allyl electrophile which then reacts with an alpha-nitroester nucleophile, ultimately leading to the formation of allylic alpha-amino esters through reduction with In powder.