Ecofriendly fast batch synthesis of dioxolanes, dithiolanes, and oxathiolanes without solvent under microwave irradiation

2,2-Dimethoxypropane and 3,3-dimethoxypentane react with 1,2-ethanediol, thio, and oxathio analogues to give the corresponding protected carbonyls in high yield under mild solvent-free conditions, These environmentally benign conditions under microwave irradiation are applied to a large-scale synthesis.