THE CYCLOADDITION REACTIONS OF UNSATURATED ESTERS WITH CYCLOPENTADIENE ON GAMMA-ALUMINA

The Diels-Alder reaction of cyclopentadiene (CP) with methyl acrylate (MA), dimethyl maleate (DMM), and dimethyl fumarate (DMF) on alumina of varying activity has been examined. The diasteroselectivity of the reaction of CP with MA is markedly dependent on the activity of the alumina. Two factors account for these changes: (1) the nature and number of the catalytic sites on the surface, and (2) the observed reversibility of the Diels-Alder reaction on the more activated alumina. The reaction of CP with MA has been used to measure the n value of the surface of unactivated alumina.