NITRATION OF HYDROGEN-CYANIDE WITH NITRYL TETRAFLUOROBORATE

The reaction of hydrogen cyanide at 0 degrees C in CFCl3, purified nit rile-free nitromethane or tetrahydrothiophene 1,1-dioxide gave dinitro gen monoxide, N2O and COn (n = 1 or 2). The same products were obtaine d in a solvent-free neat reaction of HCN(g) and NO2+BF4-(s). The exper imental data are in accord with the intermediate formation of neutral CN-NO,. This intermediate then undergoes cleavage-rearrangement to giv e N2O and CO. In a subsequent reaction carbon monoxide is oxidized by unreacted NO2+BF4- to give CO2 and the corresponding nitrosyl salt, NO +BF4-. The reaction was followed by low-temperature N-14 NMR spectrosc opy and the identity of the products established by N-14 NMR and IR sp ectroscopy. The two isomers CN-NO2 and NC-NO2 were computed ab initio at the correlated MP2 level of theory and are discussed in terms of in tramolecular stabilization by donor-acceptor interaction (negative hyp erconjugation).