Ruthenium-catalyzed cross-coupling of 7-azabenzonorbornadienes with alkynes. An entry to 3a,9b-dihydrobenzo[g]indoles

Electron-rich half-sandwich ruthenium complex CpRuI[(P[Ph.sub.3]).sub.2] has catalyzed the coupling reaction of 7-azabenzonorbornadienes with alkynes to form 3a,9b-dihydrobenzo[g]indoles. The scope and limitations of the reaction are discussed according to the substitution patterns of the alkyne and of the substituent at the nitrogen atom of the azabenzonorbornadiene.