Pyrolysis of Esters of Borneol and isoBorneol

IT is generally believed that esters pyrolyse to give the products of cis elimination in a six-membered cyclic transition state 1 . Recently, however, products corresponding to a trans elimination have been shown to be formed by the pyrolysis of methyl xanthates of some substituted cyclo hexanols 2 . The pyrolyses of xanthates and acetates of 1-alkyl cyclo hexanols give predominantly the more stable endocyclic olefins 3 , and both cis and trans elimination have been observed in pyrolyses of chlorosulphites 2 , and sulphoxides 4 .