An efficient synthesis of 1′,4′-dihydro-2′H-spiro[azetidin-2,3′-quinolin]-2′-one

A facile synthesis of 1′,4′-dihydro-2′H-spiro[azetidin-2,3′-quinolin]-2′-one is described. Synthetic highlights include simultaneous construction of azetidine ring by intramolecular alkylation and formation of spirocarbon center in excellent yield plus removal of p-methoxybenzyl (PMB) amide protective group in mild condition with good yield.