Reactivity of [C3H8N]+ ions: A combined Fourier transform ion cyclotron resonance and molecular orbital approach

✍ Scribed by G. Bouchoux; F. Penaud-Berruyer; J. Tortajada

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 856 KB
• Volume: 30
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/jms.1190300511

✦ Synopsis

The unimolecular dissociations of the two isomeric ions, [CHJCH,CHNH,I+, 1, and [CH,CHzNHCH2]*, 2, were re-examined. Molecular orbital calculations (MP2/6-311 + G**//HF/6-31G* + ZPE level) were used to characterize the corresponding potential energy profiles and, in order to understand the various kinetic effects observed, RRKM calculations were also undertaken. The experimental picture was completed by a Fourier transform ion cyclotron resonance mass spectrometry investigation on the system [ CH,CHCH, ] + + NH,. A prominent result is that the elimination of an ethene molecule from metastable ions 1 and 2 occurs via two ion-neutral complexes involving [ CH,=NH,I + and C,H, species. In the former case, this intermediate structure looks like a corner protonated cyclopropylamine. In the latter, the data confirm the earlier proposal of Bowen et ul. that the reaction is mediated by a proton-bound complex [ C,H,.--H-*-NHCH,] +.