C. Wesdemiotis, B. Leyh, A. Fura
Nov 1, 1990
Citations
0
Influential Citations
39
Citations
Journal
Journal of the American Chemical Society
Abstract
Unimolecular C-C bond rupture in oxirane leading to • CH 2 OCH 2 • is favored over C-O rupture to • CH 2 CH 2 O • , but the latter is the first-step in the lowest energy dissociation pathway through excited CH 3 CH=O to CH 3 • + • CHO. With collisional activation, • CH 2 OCH 2 • isomerizes mainly to oxirane, not methoxycarbene, :C(H)OCH 3 , while • CH 2 CH 2 O • isomerizes mainly to CH 3 CHO. All of these neutral isomers were prepared in the gas-phase via neutralization on the corresponding radical cations. Their structures, and those of their precursor cations, were established by collisionally activated dissociation (CAD), neutralization-anionization, and CAD of the mass-selected recovered molecular ions (MS/MS/MS) from neutralization-cationization. All of the neutrals and cationic isomers are found to represent stable bound structures, clarifying in particular previous contrary evidence concerning • CH 2 CH 2 O • , + CH 2 CH 2 O • , and the oxirane cation. Anionization showed the isomers • CH 2 CH 2 O − , −• C(H)OCH 3 , and −• C(OH)CH 3 to be stable