Stereoselective access to (Z)-α,γ-diazido-α,β-unsaturated esters via Lewis acid-mediated 1,3-diazidation of α,α-dimethoxy-β,γ-unsaturated esters with trimethylsilyl azide

Abstract

The synthesis of α,γ-diazido-α,β-unsaturated esters is carried out via a Lewis acid-mediated 1,3-diazidation of α,α-dimethoxy-β,γ-unsaturated esters using two equivalents of trimethylsilyl azide. The reaction proceeds in a highly stereoselective manner to provide only the (Z)-stereoisomers of the diazide products. The optimization and scope of the new method are discussed, and the utility of the products is demonstrated in the synthesis of bis-1,2,3-triazole derivatives.