A Simple Cycloaddition Approach to a Racemate of the Natural Sweetener Monatin

Abstract
The reaction of methyl 2-(3-indolylmethyl)-acrylate 2 with carbethoxyformonitrile oxide 3, followed by saponification and reduction, gives mainly racemic monatin 1. Preliminary attempts to adapt the 2+3 cycloaddition to a new chiral synthesis of monatin, is described.