Rate of Anhydride Formation in Tartrate Buffer System

Tartaric acid buffer has been shown to form a reactive intermediate in aqueous solution capable of rapidly acylating any nucleophilic compound present. With aniline as the nucleophile, the rate of formation of the intermediate, presumably an acid anhydride, has been found to proceed at roughly the same rate as that of succinic acid but slower than citric acid. Only the monoanilide was obtained in appreciable amount.