A STUDY ON THE ACTIVATION OF CARBOXYLIC-ACIDS BY MEANS OF 2-CHLORO-4,6-DIMETHOXY-1,3,5-TRIAZINE AND 2-CHLORO-4,6-DIPHENOXY-1,3,5-TRIAZINE

Activation of carboxylic function by means of 2-chloro-4,6-disubstitut ed-1,3,5-triazines 1 and 2 leading to triazine esters was found to be a multistep process with participation of quarternary triazinylammoniu m salts 3-6 as the intermediates, with the rate of reaction strongly d ependent on the structure of the tertiary amine. The studies on alkyla tion of tertiary amines with CDMT revealed the two-step process A(N) D-N, and zwitterionic addition product 9 was identified by H-1 NMR sp ectroscopy. Semiempirical modeling of the reaction as well as measured nitrogen and chlorine isotope effects also support this mechanism.