Structure and reactivity of C7H7+ ions from the decay of tritiated toluenes. 1. Reactions of free tolyl ions with methanol in the gas and liquid phases

Labeled tolyl cations from the decay of ring-multitritiated toluene have been allowed to react with methanol in the liq. and the gas phases, at pressures ranging from 6 to 100 torr, yielding Me tolyl ethers as the major products, without appreciable formation of benzyl Me ether. The isomeric compn. of the products from the gaseous systems depends on the pressure, the percentage of o-tolyl ether increasing at the expense of the para isomer as the methanol pressure is reduced. The results show that the three tolyl ions exist as distinct species in the dil. gas state. When formed in a sufficiently excited state, as from the β decay of a 3H atom in toluene, they undergo appreciable interconversion, without detectable isomerization to the benzyl cation, at least within the pressure range accessible to the decay technique.