We
have developed a protocol for efficient synthesis of indolin-2-ones
from benzofuranones and aryl amines using iodine as a mediator. A
diverse range of benzofuranones and aryl amines undergo cross-dehydrogenative
coupling and amidation of 3-aryl benzofuranones for the cascade reaction
to generate products in 24–93% yields. This reaction can be
easily scaled-up to give an indolin-2-one in a gram scale. Further
chemical manipulation of the products enabled useful transformations
of the phenol ring including alkylation, arylation, etc.