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Heterogenization of catalytically important homogeneous catalysts on solid supports has become an expanding area of research. PNN and PONOP ruthenium pincer complexes were immobilized on a silica poly(allylamine) composite, BP-1 by a two-step Mannich reaction. The complexes on BP-1 were characterized by solid state NMR, FT-IR, elemental analysis, and metal digestion studies. Model solution experiments were carried out to determine the site of electrophilic substitution on the pyridine ring of the pincer complexes and revealed substitution in both the meta - and para -position. The catalytic reactivity of immobilized (PNN)RuH(Cl)(CO) and (PONOP)RuH(Cl)(CO) on BP-1 was studied for the dehydrogenative coupling of alcohols to esters with the liberation of H 2 . Moderate to good ester yields were realized with both immobilized systems without using the base required for the homogeneous reaction and also in the presence of KOH. The homogeneous model reactions required a base for ester formation. The amine functionality on BP-1 served as the base to generate the active pincer catalyst on the BP-1 surface. Both immobilized catalysts were recycled for multiple alcohol reaction cycles. Four-step control experiments were carried out using an alcohol and both immobilized systems. The results revealed the heterogeneity of the alcohol catalysis by both BP-1-Ru-PNN and BP-1-Ru-PONOP systems. This study has opened a new catalytic methodology for reactions where base is required for catalyst activation, by using a solid support with basic functionality. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel Rh-containing non-phosphorous supported catalysts for tandem hydroformylation-hydrogenation were obtained. • Tertiary nitrogen atoms of the polymer anchored on material's surface promote aldehyde hydrogenation over Rh active centers. • Catalysts showed high activity (hydroformylation TOF 206 h−1) and chemoselectivity. • Catalyst K N performed stable hydroformylation yield at least in the first 5 cycles with a decrease in alcohol selectivity. Non-phosphorous rhodium-containing catalysts for direct conversion of olefins to alcohols via tandem hydroformylation/hydrogenation have been designed and synthesized. Interaction between Rh(acac)(CO) 2 and tertiary amino groups on the surface of mesoporous hybrid organic-inorganic supports yielded materials which were successfully used in the tandem process. Data obtained for a selected catalyst K N demonstrate that rhodium is in the Rh+1 state highly dispersed on the surface and is bonded with nitrogen atoms both before and after use. Evaluation of the catalytic performance shows high activity (hydroformylation TOF 312 h−1), chemoselectivity and stable hydroformylation yield at least in the first 5 cycles with a decrease in alcohol selectivity. The influence of temperature, reaction time, total pressure, and molar CO/H 2 ratio of syngas on oxygenate yields is described. Type of the hydroformylation active sites and possible pathways for the observed decrease in hydrogenation are discussed. [ABSTRACT FROM AUTHOR]