Copper-assisted synthesis of five-membered O-heterocycles

The reactions involving the formation of C-O bond using metal as a catalyst have emerged to be one of the most influential reactions for the synthesis of the heterocycles in modern organic chemistry. Catalysis by metals offers diverse opportunity to invent new organic reactions with promising range of selectivities such as chemoselectivity, regioselectivity, diastereoselectivity, and enantioselectivity. The methodologies used earlier for the synthesis were less approachable to the organic chemist because of their high cost, highly specified instrumentation, and inconvenient methods. For both stereoselective and regioselective formation of five-membered O-containing heterocycles, cyclic reactions that are copper-catalyzed have known to be very efficient. The present review article covers the applications of copper for the synthesis of five-membered O-containing heterocycles.