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Updated: Jun 14, 2026

Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
A fast, efficient and stereoselective synthesis of hydroxy-pyrrolidines
Emma M Dangerfield1, Shivali A Gulab, Catherine H Plunkett
1Malaghan Institute of Medical Research, PO Box 7060, Wellington, New Zealand.
Abstract:
A five-step, protecting group free synthesis of 2,3-cis substituted hydroxy-pyrrolidines is presented. Key steps in the synthesis are the chemoselective formation of a primary amine via a Vasella reductive amination using ammonia as the nitrogen source, and the stereoselective formation of a cyclic carbamate from an alkenylamine. Improvement of the reductive amination, by way of the use of alpha-picoline borane as a more environmentally benign reducing agent, is also presented.
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