29171-24-2Relevant articles and documents
The protiotetramethylammonium dication (CH3)3NCH42+: Hydrogen/deuterium exchange and calculational studies. Search for the parent protioammonium dication NH52+
Olah, George A.,Burrichter, Arwed,Rasul, Golam,Prakash, G.K. Surya
, p. 4594 - 4598 (1997)
The protonation of ammonium ions NR4+ (R = H, CH3) to form the corresponding protioammonium dications HNR42+ (R = H, CH3) was investigated by hydrogen/deuterium exchange experiments and by ab initio molecular orbital calculations. Hydrogen/deuterium exchange was observed by 2H NMR spectroscopy at the CH3 groups of tetramethylammonium ion N(CH3)4+ when reacted with excess DF:SbF5 superacid. On the basis of calculational results, the intermediacy of the corresponding C-H-protonated protiotetramethylammonium dication (CH3)3NCH42+ is suggested to account for the observed exchange. Under similar conditions, no exchange was observed in the parent ammonium ion NH4+ in FSO3D:SbF5 superacid, although the NH52+ dication was calculated to be kinetically stable with a considerable barrier to deprotonation. The pentafluoroammonium dication NF52+ was also investigated theoretically, and the results were compared to those of neutral NF5.
