Abstract
Rearrangements in cyclic and acyclic carbenium ions through hydride and methide shifts in the gas phase were investigated by MS/MS and ion neutralization/radical trapping/CAD techniques. Results indicate that: (i) there is no hydride shift on a saturated cyclohexane ring; (ii) when there is a double bond on the ring, hydride shift will take place, resulting in the formation of a more stable allylic type cation; (iii) in an acyclic hydrocarbon carbenium ion of neopentyl type, methide shift of a Wagner-Meerwein rearrangement takes place just as in solution.
