RUTHENIUM(II) SIGMA-ACETYLIDE COMPLEXES - MONOMERS, DIMERS AND POLYMERS

The complexes trans-[Ru(dppm)(2)(C=CPh(2)] and trans-[Ru(L-L)(2)C=C-R-C=C](-)(n)[L-L=bis-diphenylphosphino)methane (dppm) or bis-(diphenylphosphino)ethane (dppe), R=p-C6H4 or p-C6H2(CH3)(2)] have been prepared by the reaction of the corresponding trans-[Ru(L-L)(2)Cl-2] compound with Me(3)SnC=CPh or Me(3)SnC=C-R-C=CSnMe(3). Reactions between cis-[Ru(L-L)(2)Cl-2], acetylenes and the salt NaPF6 have yielded complexes of the type [Cl(L-L)(2)Ru=C=CPhH](PF6-)-P-+. These were converted into the corresponding mono-acetyiides, [Ru(L-L)(2)Cl(C=CPh)] by treatment with 1,8-diazabicyclo[5,4.0]undec-7-ene(DBU) or alumina. The single crystal X-ray structure of [Ru(dppe)(2)Cl(C=CPh)] confirms that during the reaction of the cis-dihalide species rearrangement takes place to give trans products.