Water in Organic Solvents: Rapid Detection by a Terbium‐based turn‐off Luminescent Sensor

Abstract Reactions carried out both in protic and aprotic water‐miscible solvents can be affected by the presence of water. We have recently discovered that the luminescence intensity of a methanolic solution of Tb(III) containing salicylic acid [Tb−SA] is highly sensitive to the water content. The water‐induced quenching of Tb(III) luminescence was utilized for the accurate measurement of water content in methanol, ethanol, acetonitrile, and tetrahydrofuran in the 0.1%–4% (v/v) range by a simple and rapid method.