Dimerisation and transannular reactions of cycloalkenes on H-mordenite

Abstract

A series of cycloalkenes were adsorbed onto activated H-mordenite, and their transformations investigated with EPR. This technique monitors the catalytic transformations which occur, by detecting the radical cations formed from unsaturated intermediates with low ionisation potentials. Cyclopentene and cyclohexene were found to take part in dimerisation and ring enlargement reactions. Medium sized rings, cyclooctene and cyclodecene underwent transannular ring closure, as did cyclododecene, to form bicyclo[n.n.0]alkenes (n= 3, 4, 5).