A formal [5 − 1 + 2] annulation for the preparation of substituted α-pyrones is reported. The reaction involves the decarbonylative coupling of substituted maleic anhydrides with internal alkynes in the presence of a rhodium(III) catalyst and a copper(II) salt, affording tri- and tetrasubstituted α-pyrones.
据报道,正式的[5-1 + 2]环化法制备了取代的
α-吡喃酮。该反应涉及在
铑(III)催化剂和
铜(II)盐存在下,取代的
马来酸酐与内部
炔烃的脱羰基偶联,得到三和四取代的
α-吡喃酮。