The hydrogenation of 1 over 10% palladium on charcoal proceeds to give seven products (2- 8). Alkene 2 is the precursor of the other products. A concerted process including hydrogenation, hydrogenolysis, and isomerization is postulated to account for the direct formation of 5 from 2. The effect of added nitrogen bases on the product distribution ic; presented, and several mechanistic alternatives are discussed.
