title: Superelectrophilic protio methyl- and protio dimethylmethyleniminium dications.
abstract: Electronic structures and energies of superelectrophilic dications derived by protonation of methyl- and dimethylmethyleniminium (R'R' 'C=N+R'R' '; R', R' ' = CH3 or H) ions were calculated at the ab initio MP2/6-311+G level. The calculations identified the N-protonated isopropyleniminium dication 14 as a minimum structure. On the basis of computed energies, deprotonation energies of the global minimum structures were also calculated. The 13C NMR chemical shifts of the intriguing dication 14 were calculated using the GIAO-MP2 method. The 13C NMR chemical shifts of the isoelectronic analogue tert-butyl cation were also calculated at the same level in order to explore the effect of an additional charge in dications 14.
authors.affiliation: Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, University Park, Los Angeles, California 90089-1661, USA. olah@usc.edu
authors.forename: George A
authors.initials: GA
authors.lastname: Olah
authors.forename: G K
authors.initials: GK
authors.lastname: Surya Prakash
authors.forename: Golam
authors.initials: G
authors.lastname: Rasul