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The trimethoxysilyl-(T)-functionalized ruthenium(II) complex cis-Cl(H)Ru(CO)(P∼O) 3 [2(T 0 ) 3 ] (P∼O: Pcoordinated ether-phosphine) is sol-gel processed with tetraethoxysilane (TEOS, Q 0 ) and aluminum 2-propanolate [Al(OiPr) 3 ]. All components are simultaneously polycondensed to result in the poly(alumosiloxane)-bound ruthenium complexes A and B with various amounts of aluminum. From 31 P and 13 C CP MAS NMR as well as IR spectroscopy it can be concluded that the complex fragment cis-Cl(H)Ru(CO)(P∼O) 3 is preserved during the immobilization. Polymers A and B show a remarkable number of Si-O-Al bonds in the 29 Si solid state NMR spectra. The aluminum is incorporated as tetrahedrally coordinated AlO 4 units with a formal negative charge. The 6-fold coordinated AlO 6 groups containing water and hydroxide groups as ligands are sited as interstitials and act as their counterions. Stoichiometric formulas of A and B derived by 27 Al and 29 Si solid state NMR spectroscopy and energy dispersive X-ray spectroscopy (EDX) suggest that the amount of aluminum can be adjusted by the applied stoichiometry. The two materials A and B act as hydrogenation catalysts of transcrotylaldehyde and are easy to separate from the reaction mixture by simple centrifugation.

The reaction of the functionalized ether-phosphane ligand CH,0(CH,),P(Ph)(CH,)3Si(OMe)3 (lc) with C~, R U ( P P~~)~ (2) and HRuC~(CO)(PP~~)~ (3) results in the formation of the monochelated (ether-phosphane)ruthenium(II) complex Cl,Ru(P-O),(PnO) (4c) and the hydride HRuCl(CO)(P-O), (5c) (P-O: ql-P-coordinated; P"0: $-O"P-coordinated). Compounds 4c and 5c are polycondensated to the corresponding polysiloxane-bound complexes 4c' and 5c'. 31P-chemical shifts of the immobilized species 4c' and 5c' in the solid-state CP-MAS NMR spectra are compared with those of the 31P{1H)-NMR spectra of monomeric complexes 4b, c and 5b, c with the ligands CH30(CH2)2P(Ph)(CH2)3SiMe3 (1 b) and 1 c in solution. No change in the structure between the monomeric and polymeric species could be observed. According to "Si CP-MAS NMR-spectroscopic investigations the polysiloxane chains are connected by ruthenium complexes to a network with favourable properties. The chelated polysiloxane-bound red complex 4c' adds CO in the solid state to give quantitatively yellow Qll-trQnS-ClzRU(Co),(P -O), (6 c'). In the presence of carbon monoxide there is an equilibrium between 5c' and HRuCl(CO),(P-O), (7c') which was also found in solution for 5b, c and 7b, c. The reactions indicate that the chemistry of polysiloxane-bound ether-phosphane complexes can well be compared with the chemistry in solution. 31P CP-MAS NMR spectra of the complexes 4c' and 5c' are strongly dominated by a chemical shift anisotropy which shows a fingerprint pattern both for monomeric crystalline complexes 4a, 5a [containing ligand Ph2P (CH&0CH3 (1 a)] and polysiloxane-bound phosphane complexes 4c' and 5c'.