Stereochemistry of an Ene Reaction involving 1,7-Dienes; Bicyclononanes from (3-Cyclohexenyl)diallylcarbinols

Article abstract of DOI:10.1002/hlca.19840670124

(3-Cyclohexenyl)diallylcarbinols undergo a thermal retro-ene reaction to give crotonylcyclohexenes at ca. 200 degC.A side-reaction is an ene reaction to give bicyclo<3.3.1>nonanes.These become the main products above 300 degC.The stereochemistry of 2-allyl-1,4,6-trimethylbicyclo<3.3.1>-6-nonen-2-ols and related compounds is discussed, and a case is described in which the allyl group is not freely rotating.