Copper(I)-Catalyzed One-Pot Synthesis of 2<i>H</i>-1,4-Benzoxazin-3-(4<i>H</i>)-ones from <i>o</i>-Halophenols and 2-Chloroacetamides

We developed an efficient and convenient method for preparing N-substituted 2H-1,4-benzoxazin-3-(4H)-ones from 2-halophenols via a nucleophilic substitution with 2-chloroacetamides followed by a CuI-catalyzed coupling cyclization. A broad spectrum of substrates can be effectively employed to afford the desired products in good yields. Since this method involves simple reaction conditions, a short reaction time, and a broad substrate scope, it is particularly attractive for the efficient preparation of biologically and medicinally interesting molecules.