T. Mitsudo et al., RUTHENIUM COMPLEX-CATALYZED DIMERIZATION OF NORBORNADIENE TO PENTACYCLOTETRADECADIENE, Journal of the Chemical Society, Chemical Communications, (4), 1994, pp. 435-436
[Ru(cod)(cot)] catalyses an unusual dimerization of norbornadiene to g
ive (1,7).1(3,6).0(10,13).0(12,14)]tetradeca-4,8-diene in high yield (
85%) with high selectivity, the structure of which is established by X
-ray analysis of its brominated derivative, .0(10,13).0(12.14)]-4,5,8,
9-tetrabromotetradecane, to have five five-membered rings as a result
of multi-carbon-carbon bond activation.