Aggregation-induced C-C bond formation on an electrode driven by the surface tension of water.

Electrochemical organic synthesis is typically conducted in organic media. The solvent and related supporting electrolytes negatively affect the greenness of electrosynthesis. In this work, with 100% water used as the solvent, we realize aggregation-driven electrochemical radical cross coupling of unsaturated compounds driven by water tension. A key finding is that aggregation of the substrate at the electrode confined the radical intermediate and prevented side reactions, thus providing a way to regulate radical reactions in addition to their native properties. The reaction provides up to 90% yields with almost quantitative chemoselectivity. The pure water system readily yields the products via cold filtration, and the solvent is recycled repeatedly. In particular, the life span of the radical species generated in the reaction increase significantly because of the confined environment in the aggregation state. The greenness of this protocol is further enhanced with readily separation of product from media using cooling and filtration.