Investigation of the conversions of 1,3-cyclohexadiene and 1, 4-cyclohexadiene in the presence of skeletal catalysts of cobalt and nickel

Abstract

1. Skeletal cobalt and nickel catalyze the conversion of cycloolefins at room temperature. In the mixture, 1, 3-cyclohexadiene reacts first, then 1, 4-cyclohexadiene, the latter forming cyclohexene. 2. In the presence of hydrogen on both catalysts, 1, 3-cyclohexadiene disproportionates and is hydrogenated, forming cyclohexene. The unconjugated diene is also hydrogenated, but practically does not disproportionate. In an atmosphere of nitrogen both cyclohexadienes disproportionate. 3. Under conditions of hydrogenation, with increasing amount of the nickel catalyst the ratio disproportionation: hydrogenation increases, probably as a result of a decrease in the hydrogen concentration on the catalyst and an increase in the fraction of the surface free of hydrogen, on which the diene can be dehydrogenated.