1. Cyclic Dienes. IX. Synthesis of 1,2-Dimethylene-4-cyclohexene1,2
2. The Conformation of a Six-membered Ring cis-1,2 Fused to a Five-membered Ring1
3. We are indebted to Dr. J. Hartenstein for these dehydration experiments.
4. Hydrogenation over palladium-charcoal gave cis decahydroisoquinoline (b.p. 80–82°/18 mm; hydrochloride m.p. 180–181°) identical with a sample obtained by hydrogenation of isoquinoline (B. Witkop, J. Amer. Chem. Soc. 70, 2617 (1948) and separation of the cis and trans isomer by preparative VPC.