Charge distribution between formally identical fragments: The retro Diels-Alder cleavage
作者:F. Turecček、V. Hanuš
DOI:10.1002/oms.1210150104
日期:1980.1
AbstractThe electron impact induced retro Diels‐Alder cleavage of 4‐vinylcyclohexene, 1,4‐dimethyl‐4‐vinylcyclo‐hexene, limonene, dicyclopentadiene and dicyclohexadiene has been investigated using deuterium labelled analogues. With limonene, dicylopentadiene and dicyclohexadiene the charged diene fragments are produced with the same probability from both subunits of the molecular ion. With 4‐vinylcyclohexene and 1,4‐dimethyl‐4‐vinylcyclohexene, diene fragments containing the former vinyl group are charged preferentially. This small asymmetry of charge distribution was found to be independent of the ionizing energy. A new, qualitative rationalization is suggested to account for the unsymmetrical charge distribution in 4‐vinylcyclohexene and 1,4‐dimethyl‐4‐vinylcyclohexene. Metastable spectra and hydrogen scrambling are discussed.