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The reaction of biphenylene with various nitriles in the presence of catalytic amount of [Rh(cod)2BF4]/dppe under microwave irradiation afforded 9-substituted phenanthridines. The reaction with alkyl and aromatic nitriles provided the corresponding 9-substituted phenanthridines in 26–79% isolated yields. The reaction was also carried out with cyanopyridines and it provided heterocyclic compounds with the bipyridine and terpyridine scaffold. The synthesized bipyridine and terpyridine were complexed with [Rh(cod)Cl]2. The former provided a Rh(III) complex in which the cyclooctadiene moiety was oxidized to the tetrahydrofuran ring, whereas the latter gave a structurally fluxional complex (in solution) with only one pyridine ring coordinated to the rhodium atom.

Dibutyl zirconocene-mediated TRANS-selectivecyclization of methoxyallyl-ene followed by the reaction with electrophiles isa convenient method for the synthesis of functionalized cyclopentanederivatives. Ring-closing metathesis of the obtained cyclopentanederivative yielded a common building block for the synthesis ofsesquiterpene analogues with unnatural TRANS-[3.4.0]bicyclo-nonaneskeleton.