[Reaction: see text] The stereoselective preparation of (E)- or (Z)-trisubstituted alpha,beta-unsaturated esters in three steps from N-protected glycine is presented. The key step in the synthesis is the highly selective enol tosylation of gamma-amino beta-keto esters. The enol tosylates are stable, crystalline compounds that undergo smooth and effective Suzuki-Miyaura coupling reaction with a variety of aryl boronic acids.
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