Catalyst-free aza-Michael addition of azole to β,γ-unsaturated-α-keto ester: an efficient access to C-N bond formation

An efficient aza-Michael addition of azoles to beta,gamma-unsaturated-alpha-keto esters under room temperature conditions has been developed. In this conjugate addition, no additional catalyst is employed. Azole reacts with beta,gamma-unsaturated-alpha-keto ester smoothly to afford new C-N bond adducts in good to excellent yields (up to 96%). (C) 2012 Elsevier Ltd. All rights reserved.