Gas-phase rearrangements of deprotonated ketoximes, ketoxime ethers, and aldoximes. A negative-ion beckmann rearrangement
Abstract
Evidence is presented which indicates that the pronounced loss of water from deprotonated ketoximes involves specific proton transfer followed by a negative-ion Beckmann rearrangement. For example, Me2CNO–→–CH2(Me)C
NOH[graphic omitted][(CH2
C
NMe)–OH]→ CH2
C
NCH2–+ H2O. Deprotonated aldoximes, e.g. MeCH
NO–, fragment in this way, but also undergo the competing process MeCH
NO–→ Me
NOH →[(MeCN)–OH]→–CH2CN + H2O. Other rearrangements occur when proton transfer to oxygen does not occur; e.g. Ph2C
NO– [graphic omitted] Ph
NOPh → PhO–+ PhCN.