A convenient and practical hydrosulfonylation and disulfonylation of substituted maleimides was realized using sulfonyl hydrazides as the sulfur reagent and tert-butyl hydroperoxide as the oxidant. The advantages of the reactions include mild and transition-metal-free reaction conditions, good functional group tolerance, and readily available starting materials. The radical species-induced pathway is also demonstrated by mechanistic studies.

Bis(indolyl)methanes were synthesized by a green protocol. Primary structure–activity relationship analysis showed that the bisindolyl structure is essential for CES2 inhibition.

By employing Cu(CH 3 CN) 4 PF 6 as the catalyst and tert-butyl hydroperoxide as the oxidant, we realized a threecomponent radical selenosulfonation of substituted maleimides, sulfonyl hydrazides, and diphenyl diselenides, providing a series of 3,4-selenosulfonylated succinimides in moderate to good yields. This reaction features broad substrate scopes, high functionalgroup tolerability, and feasibility of gram-scale synthesis, enabling one-step construction of C−SO 2 and C−Se bonds under mild reaction conditions. Preliminary mechanistic studies support the free-radical-induced pathway.