Electron spin resonance of transient radicals during pyrolysis and photolysis. Benzyl ether

Benzyl ether has been pyrolyzed at 452, 474, and 4970C at a pressure of 20.7 MPa. Benzyl has been observed by ESR, and product analyses have been made. The reaction C6H5CHOCH2C6H5 → C6H5CHO + C6H5CH2 is part of a proposed scheme. This reaction was separately studied photolytically by preparing the reactant radical with benzyl ether and an initiator in benzene solution. Measurements from 105 to 1550C at 6.9 MPa gave an activation energy of 15.5 kcal/mol (+-15%) and an estimate of the Arrhenius A factor of 1 x 1012 s-1. The various results are discussed in terms of a free-radical chain reaction. Methylcyclohexadienyl was also prepared, and ESR parameters are given