PROTIO-2-PROPYL DICATION (PROPANE DICATION, C3H82- HYDROGEN() )DEUTERIUM EXCHANGE AND THEORETICAL-STUDY - DIFFERENTIATION OF REACTIVE GITONIC (PROXIMAL) FROM STABLE DISTONIC (DISTANT) DICATIONS AND THE PROTOSOLVOLYTIC ACTIVATION OF CARBOCATIONS/

Authors
OLAH GA HARTZ N RASUL G PRAKASH GKS BURKHART M LAMMERTSMA K
Citation
Ga. Olah et al., PROTIO-2-PROPYL DICATION (PROPANE DICATION, C3H82- HYDROGEN() )DEUTERIUM EXCHANGE AND THEORETICAL-STUDY - DIFFERENTIATION OF REACTIVE GITONIC (PROXIMAL) FROM STABLE DISTONIC (DISTANT) DICATIONS AND THE PROTOSOLVOLYTIC ACTIVATION OF CARBOCATIONS/, Journal of the American Chemical Society, 116(8), 1994, pp. 3187-3191
Citations number
54
Categorie Soggetti
Chemistry
Journal title
Journal of the American Chemical Society → ACNP
ISSN journal
00027863
Volume
116
Issue
8
Year of publication
1994
Pages
3187 - 3191
Database
ISI
SICI code
0002-7863(1994)116:8<3187:PD(DCH>2.0.ZU;2-0
Abstract
Hydrogen/deuterium exchange was observed by H-2-NMR spectroscopy for t he long-lived 2-propyl cation when treated with DF in SbF5/SO2ClF at - 78 degrees C. As under long-lived stable ion conditions at low tempera tures no deprotonation equilibria exist for alkyl cations, protio (deu terio) solvation involving the intermediacy of the protio(deuterio)-2- propyl dication is suggested to account for the exchange. Ab initio ca lculations at the MP4SDTQ/6-31G*//MP2(FU)/6-31G** level show the prot io-2-propyl dication, a gitonic (proximal) dication (as contrasted wit h usual distonic (distant) dications), to be a remarkably stable minim um structure and support the suggested mechanism for the observed isot opic scrambling.