A facile and expedient route for the synthesis of 2‐ethoxy‐ and 2‐(ethylcarboxylate)‐(4H)‐3,1‐benzoxazine‐4‐ones is described using guanidinium chloride as a safe and convenient dehydrocyclizationagent. High yields of the products obtain under mild reaction conditions without need to use of any catalyst and with easy work‐up of the reaction mixture.