DINUCLEAR SILYLENE BRIDGED CYCLOPENTADIEN YLRHODIUMBIS(ETHENE) COMPLEXES, PHOTOCHEMICAL-REACTION WITH BENZENE-DERIVATIVES, AND SELECTIVE INCLUSION OF METHYLCYCLOPENTANE INTO THE CRYSTAL-LATTICE OF [ME(2)SI(3-BU(T)-C5H3RH(C2H4)(2))(2)]

By reaction of [[(C2H4)(2)RhCl](2)] with Na-2[Me(2)Si(C5H4)(2)] or wit h Li-2[Me(2)Si(3-Bu(t)-C5H3)2] in THF the dinuclear silylene bridged c omplexes [Me(2)Si{C5H4Rh(C2H4)(2)}2] 1 and [Me(2)Si{3-Bu(t)-C(5)H(?)3R h(C2H4)2}2] 2, respectively, were synthesized. Due to the asymmetric s ubstitution of the five-membered rings and their hindered rotation aro und the Si-C axes, 2 is formed as three isomers. The X-ray structure a nalysis of 2 obtained from hexane reveals the selective inclusion of m ethylcyclopentane, the content of which in the solvent is about 17%, i nto the crystal lattice. UV irradiation of 1 in hexane in the presence of benzene causes elimination of the ethene ligands yielding the mu-e ta 3:eta(3) benzene complex [Me(2)Si(C5H4Rh2)(2)C6H6] which cannot be separated from unreacted 1. However, separation is possible in case of the hexamethylbenzene compound 4 analogous with 3.