Scalable Synthesis of β-Amino Esters via Reformatsky Reaction with N-tert-Butanesulfinyl Imines

Abstract

The Reformatsky reagents derived from ethyl bromoacetate and tert-butyl bromoacetate add cleanly, in high yield, and with good diastereoselectivity to N-tert-butanesulfinyl aldimines and ketimines. Importantly, this reaction scales well (>50 mmol), and affords products upwards of 70% yield over three steps, starting from commercially available N-tert-butanesulfinamide, aldehydes, and ketones.