An Unusual Dimerization in the Nitrosation Reaction of a Caryophyllene-type α,β-Unsaturated Oxime

The treatment of two isomeric α,β-unsaturated oximes derived from the sesquiterpene hydrocarbon caryophyllene with nitrous acid, generated in situ from sodium nitrite and acetic acid, results in the formation of an unusual dimeric product whose structure was determined by X-ray crystallographic analysis.