An environmentally benign synthesis of Tetrabutylphosphonium tribromide (TBPTB) – a versatile and efficient phase transfer reagent for organic transformations

Tetrabutylphosphonium tribromide (TBPTB), a mild and versatile reagent, has been synthesized following an environmentally benign protocol. The new reagent possesses inherent phase transfer properties which facilitates organic reactions in aqueous medium. Thermal stability of the reagent which enables organic reactions under microwave irradiation and recyclability of the spent reagent are special attributes of the new reagent. These properties collectively provide an opportunity for facile, practical, and eco-friendly synthesis of a wide range of pharmaceutically significant and specialty organic compounds such as bromo-organics, isothiocyanates, cyanamides and 2-aminobenzothiazoles in excellent yields on-water under microwave irradiation.