Three-Component Diastereoselective Synthesis of Imidazooxazines

Significance

Starting from readily available imidazole and pyridine aldehyde precursors, an efficient one-pot, three-component synthesis of ­substituted 1,8a-dihydro-7H-imidazo[2,1-b][1,3]oxazine derivatives in excellent yields is reported. The reaction occurs under neutral conditions, requires no additives for activation and, interestingly, is highly diastereoselective.