1-cyclohexyloctane is isomerized on the large pore, bifunctional zeoli
te catalyst Pt/H-Y. The detailed isomerization mechanism of this napht
ene molecule is revealed through a thorough analysis of the numerous i
somerization products. It is found that methyl side-chains are generat
ed on the ring of the molecule via a ring contraction-expansion mechan
ism, which are subsequently transferred to the n-alkyl substituent via
methyl shifts. Direct branching of the n-alkyl chain is a much slower
process compared to the generation of methyl substituents on the ring
.