Acid-assisted hydrogenation of CO₂ to methanol using Ru(ii) and Rh(iii) RAPTA-type catalysts under mild conditions

Abstract

A highly efficient homogeneous catalyst system for production of CH3OH from CO2 using single molecular defined ruthenium and rhodium RAPTA-Type catalysts [Ru(ƞ6-p-cymene)X2(PTA)] (X=I(1), Cl(2); PTA=1,3,5-triaza-7-phosphaadamantane and rhodium catalysts [Rh(ƞ5-C5Me5)X2(PTA/PTA-BH3)] (X=Cl(3),...

Recent developments in first-row transition metal complex-catalyzed CO2 hydrogenation

“…4). 50 Thus, the heavy transition metal-containing catalysts paved the way for optimized CO 2 hydrogenation to methanol conversion protocols while providing an insight into the structure–function relationship. This information set the template for designing 3d-metal-based catalysts in an attempt to replicate their excellent reactivity.…”

Beyond transition block metals: exploring the reactivity of phosphine PTA and its oxide [PTA(O)] towards gallium(iii)

“…4 This has prompted extensive synthetic chemistry investigations, giving rise to the development of a wide number of organometallic transition metal compounds with photoluminescence properties and mostly active in catalysis under homogeneous aqueous or biphasic conditions. Typical catalytic reactions carried out in the presence of PTA (or PTA-based analogues) include hydrogenations and transfer hydrogenations, [5][6][7][8] hydroformylations and hydrosilylations, [9][10][11][12] allylic isomerization 13,14 and organonitrile hydration. 15,16 In parallel, the high stability and water solubility of PTA make it also an attractive scaffold to be incorporated into compounds and formulations for biomedical use.…”

Direct valorization of biomass waste to gamma-valerolactone

“…By using a novel combination of Ru-MACHO-BH, H2, and weak acid H3PO4(aq), the myriad of cascade steps from biomass to GVL performs highly efficiently and selectively under mild reaction conditions (Figure 2). Notably, there exist relatively few examples of homogeneous catalytic hydrogenations under acidic conditions [18][19][20][21][22][23][24] . Furthermore, the Noyori-type PNP pincer complexes 25 , such as the Ru-MACHO complex 26 and analogs, have demonstrated excellent activity in both basic [27][28][29] and neutral media [30][31][32][33] , but to the best of our knowledge, never under Brønsted acid conditions.…”