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The T—silyl functionalized diamine‐bis(ether‐phosphine)ruthenium(II) complexes 1a(T°) — 1g(T°) (Scheme 1) were sol‐gel processed in the presence of different amounts of the co‐condensation agents CH3Si(OMe)3 (Me—T°) and (MeO)2SiMe—(CH2)6—MeSi(OMe)2 (D°—C6—D°) to produce a library of the interphase catalysts X1a — X1c, X2a — X2g, and X3a — X3g. Due to the remarkable electronic and steric effects of the co‐ligands on the catalytic activity of such complexes, a series of aliphatic and aromatic diamines was selected. The new polymers were investigated by multinuclear CP/MAS solid‐state NMR spectroscopy as well as by EXAFS, EDX, SEM, and BET methods. Selected interphase catalysts show high activities and selectivities in the hydrogenation of trans‐4‐phenyl‐3‐butene‐2‐one.

Nanostructured, mesoporous inorganic–organic hybrid xerogels were reproducibly synthesized by a sol–gel procedure. For the introduction of long alkyl chains into inorganic polymers, trifunctional n‐alkyltrialkoxysilanes of the type CH3(CH2)nSi(OR)3 (n = 7, 11, 17; R = CH3, C2H5) were co‐condensed with Si(OEt)4 (TEOS). The synthetic pathway involves the employment of n‐hexadecylamine as template and catalyst. The xerogels obtained by the present procedure consist of uniform spherical particles with a diameter of about 1 μm. The composition of the new materials was determined by 13C and 29Si cross polarization magic angle spinning (CP/MAS) NMR spectroscopy. In addition, the degree of organization was investigated by small angle X‐ray and electron diffraction. In accordance with 13C CP/MAS NMR spectroscopic measurements, the alkyl chains form a crystalline arrangement within the silica polymer. Brunauer–Emmett–Teller (BET) adsorption measurements confirm specific surface areas of up to 1400 m2/g. The material properties prove the xerogels to be suitable as stationary phases in high‐performance liquid chromatography (HPLC). These novel mesoporous, nanostructured materials have been successfully employed in HPLC for the first time. Different standard reference materials (SRMs) containing polycyclic aromatic hydrocarbons have been separated with the xerogels described in the present work.

Keywords: Iridium / Immobilization / Sol-gel processes / Accessibility studies / NMR spectroscopyThe synthesis of the T-silyl functionalized, and therefore solgel processable, Vaska complex [IrCl(CO){(C 6 H 5 ) 2 PC 6 H 4 -(CH 2 ) 4 Si(OMe) 3 } 2 ] [4(T 0 )] succeeded by reaction of [Ir(µ-Cl)(COE) 2 ] 2 (COE = cyclooctene; 1) with the phosphane (C 6 H 5 ) 2 PC 6 H 4 (CH 2 ) 4 Si(OMe) 3 [3(T 0 )] in the presence of carbon monoxide. Subsequently, 4(T 0 ) was co-polycondensed with five equivalents of (MeO) 3 Si(CH 2 ) 3 C 6 H 4 (CH 2 ) 3 Si(OMe) 3 {5[Ph(1,4-C 3 T 0 ) 2 ]} to give the polysiloxane-bound complex X1. For accessibility studies of the reactive centers, X1 was

Novel co-condensing agents of the type R'Si(OMe) 2 (CH 2 ) 3 R 2 Si(CH 2 ) 3 Si(OMe, R~Et, R'~OMe} were synthesised by hydrosilylation of the corresponding diallyldialkylsilanes 1, 2 with dichloro(methyl)silane and trichlorosilane, respectively, followed by treatment with trimethyl orthoformate. These precursors were sol-gel processed with or without PhSi(OMe) 3 [Ph(T 0 )] to give the xerogels X3a-d, X4a-d. The polysiloxane matrices, the degree of condensation and the integrity of the hydrocarbon backbone were investigated by means of solid state NMR spectroscopy ( 13 C, 29 Si). To study the polymer dynamics in the dry state 29 Si CP/MAS NMR measurements of relaxation times (T 1rH ) and crosspolarisation parameters (T SiH ) were carried out. 1 H HR/MAS NMR experiments and T 1rH measurements in different solvents were undertaken to get information on the mobility of the polymers in suspension. Scanning electron microscopy (SEM) images show the morphology of the polymers and energy dispersive X-ray spectroscopy (EDX) suggests that the distribution of the elements agrees with the applied stoichiometry.