We have developed an efficient and green strategy for the synthesis of C2-amino indolin-3-ones and C2-acyloxy indolin-3-ones via KI-catalyzed C(sp3)-H amination and acyloxylation of indolin-3-ones using air as the oxidant. The reaction provides straightforward access to 2-substituted indolin-3-ones by the direct functionalization of indolin-3-ones at the C2 position under mild conditions. Moreover, the conditions enable direct functionalization of a range of complex pharmaceuticals, providing attractive products for medicinal chemistry programs.