Synthesis of 2-amino-4 H -1,3-oxazines and 2-amino-4 H -1,3-thiazines through a Yb(OTf) 3 -assisted, acid-catalyzed one-pot cyclocondensation reaction

n efficient synthesis of 2-amino-4,6-diaryl-4 H -1,3-oxazine and 2-amino-4,6-diaryl-4 H -1,3-thiazine derivatives has been demonstrated through a one-pot multicomponent cyclocondensation reaction. Ytterbium triflate and concentrated HCl has been utilized as the catalyst system for this reaction. The method produced good to excellent product yields and allowed a wide variation of the substituents in both aryl moieties.