N‐Benzoyl‐4‐dimethylaminopyridinium Chloride: A Lewis Base Adduct for Efficient Poly and Monobenzoylation

N‐benzoyl‐4‐dimethylaminopyridinium chloride [DMAPBz]+Cl− was efficiently employed for polybenzoylation of triols and tetrols without epimerization and elimination products. This Lewis base adduct has also been employed for regioselective monobenzoylation of polyols obtained from D‐pentoses. Further an eco‐friendly monobenzoylation of phenols, amines and alcohols was achieved in water as a solvent without using a base and chromatographic purification of the products. Chemoselective monobenzoylation and recovery of the DMAP is an added advantage of our protocol. A new Lewis base adduct [DMAPBz]+Cl−, was prepared and employed for polybenzoylation of chiral tetrols and triols without racemization and elimination. The reagent also used for regioselective monobenzoylation of tetrols, triols and diols. Phenols, amines and alcohols were also efficiently benzoylated using the same reagent in water. Chemoselectivity and recovery of DMAP are an added advantage to our protocol.