Synthesis of cis-α-Bisabolene

Department of Chemistry, Panjab University, Chandigarh-160 014

Manuscript received 28 August 1987, accepted 30 October 1987

The nitrite, 3-(4'-methylcyclohex-3'-en-1-yl)but-2-enylcyanide (3) was procured by the reaction of cuprous cyanide In DMSO on 3-(4'-methylcyclohex-3'-en-1-yl)but-2- enyl bromide (2). On alcoholysis, the above cyanide furnished methyl 4-(4'-methyl­cyclohex-3'-en-1-yl)pent-3-enoate (4) which was smoothly reduced to the corresponding carbinol (5). The key intermediate, 4-methylcyclohes-3'-en-1-yl)pent-3-en 1-al (6) was prepared by the oxidation of the carbinol (5) with CrO₃/Py which upon Wittig reaction with isopropylldene triphenyiphosphorane gave cis-α-bisabolene.