H/D exchange reactions of protonated diglycine; an electrospray ionization–flow tube reactor experiment

Abstract

The H/D exchange reactions of protonated diglycine, GLY 2H +, with ND 3 were studied under thermal conditions with a combination of an electrospray ion source and a flow tube reactor. Consecutive exchange of the five labile hydrogens is observed with increasing flow rate of ND 3. Collision complexes corresponding to the consecutive H/D exchanges are monitored for the first time. The role of multiple exchanges in a single collision event with ND 3 is probed. Results will be discussed in the light of previously suggested mechanisms of H/D exchange of GLY 2H + with deuterated ammonia.