O-Propargyl carbamates 1 undergo an intramolecular nucleophilic addition to acetylenic bond at the nitrogen atom to furnish 4-methylene-2-oxazolidinones 2 in good yields in the presence (Cu+ for R1 = p-toluenesulfonyl, Ag+ for R1 = acyl) or absence (for R1 = alkyl and aryl) of a transition metal catalyst.
O-丙炔基氨基甲酸酯1在氮原子上的炔键上进行分子内亲核加成,从而以高收率提供4-亚甲基-2-恶唑烷酮2(Cu + R 1 =对甲苯磺酰基,Ag + R 1 =酰基)或不存在(对于R 1 =烷基和芳基)的过渡金属催化剂。