Diastereoselective reduction of 2,3-dioxo-4-carboxy-5-substituted pyrrolidines using NaBH4/AcOH and heterogenous hydrogenation reactions

Abstract

Diastereoselective reduction of 2,3-dioxo-4-carboxy-5-(substituted)pyrrolidine 1 by NaBH4/AcOH and heterogenous hydrogenation were reported. Stereochemical assignment and diastereomeric ratios of the products were determined using 1H NMR and single crystal X-ray analyses. The steric factors of the C-5 substituents of the pyrrolidinone was shown to have an interesting influence on both the yield and diastereoselectivity of the reduced product.