Synthesis of Oxazolidines and Dihydroxazines via Cyclization of α-Aminated Ketones.

A new approach to oxazolidines and dihydroxazines was developed by regioselective cyclization of α-aminated ketones under transition metal-free conditions. Oxazolidine derivatives were generated in the presence of chloro benziodoxole and TFA, while dihydroxazines were formed without a hypervalent iodine reagent. The reaction was performed under room temperature and gave the products in good to excellent yields.