Intramolecular 1,2-alkyl shifts in unsymmetric dialkoxycarbenes studied by very low vapour pressure (VLVP) pyroiysis mass spectrometry

Methoxy-(2,2,2-trifluoroethoxy)carbene radical cations, CH 3 O-C-OCH 2 CF 3 •+ , 1 •+ , are cleanly generated by the dissociative electron ionization (EI) of 2-methoxy-5,5-dimethyl-2-(2,2,2-trifluoroethoxy)-Δ 3 -1,3,4-oxadiazoline I. Neutralization–reionization (NR) mass spectrometry of the neutral carbene 1, generated by one-electron reduction of 1 •+ , shows no recovery ion signal and thus 1 is not a viable species within the μs time scale of …