Generation and reactivity of a new heterocyclic silylene, a silaazaanthracene

The cyclic silylene 6, a silaazaanthracene derivative, which possesses 14-e lectrons, has been generated by the reduction of 10, 10-dichloro-5-methyl-5 ,10-dihydrophenazasiline (5) with lithium naphthalenide. Reactions of 6 wit h 2,3-dimethyl-1,3-butadiene, isoprene, and triethylvinylsilane gave the co rresponding silylene-trapping products, 7, 8, and 9, in moderate yield. Pse udoaromatic stabilization of the cyclic silylene 6 was not observed possibl y due to the fact that the three rings are not coplanar.