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Updated: May 11, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
(L)-(Trimethylsilyl)alanine synthesis exploiting hydroxypinanone-induced diastereoselective alkylation
A René1, N Vanthuyne, J Martinez
1IBMM, UMR-CNRS-5247, Universités Montpellier I and II, Place Eugène Bataillon, 34095 Montpellier, France.
Abstract:
A new and efficient synthesis of (L)-(trimethylsilyl)alanine (TMSAla) with suitable protection for use in Solid Phase Peptide Synthesis (SPPS) has been accomplished starting from glycine tert-butyl ester and using hydroxypinanone as chiral inductor. The silylated side chain was introduced by alkylation of the Schiff base intermediate with iodomethyl(trimethylsilane) at -78 °C. Among the different synthetic routes that were tested including several chiral inductors and different Schiff bases, this strategy was selected and afforded (L)-TMSAla in good chemical overall yield with 98 % ee.
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