TY  - JOUR
AB  - Two distinct proton exchange reactions occur in metastable gaseous benzylbenzenium ions, generated by isobutane chemical ionization of diphenylmethane and four deuterium-labelled analogues. Whereas the proton ring-walk at the benzenium moiety is fast giving rise to a completely random intraannular proton exchange, the interannular proton exchange is surprisingly slow and competes with the elimination of benzene. A kinetic isotope effect of kH/kD= 5 has been determined for the interannular proton transfer, and a particularly high energy barrier of 50-75 kJ mol-1 has been estimated. These observations are attributed to steric restrictions of the ring-to-ring proton transfer in benzylbenzenium ions and contrasted to the fast interannular proton exchange in the higher homologues.
DA  - 1986
DO  - 10.1002/oms.1210210802
LA  - eng
IS  - 8
M2  - 451
PY  - 1986
SN  - 0030-493X
SP  - 451-457
T2  - Organic Mass Spectrometry
TI  - Inter- and intra-annular proton exchange in gaseous benzylbenzenium ions (protonated diphenylmethane)
UR  - https://nbn-resolving.org/urn:nbn:de:0070-pub-17742136
Y2  - 2024-11-22T05:10:04
ER  -