Directly Knitted Ruthenium Pincer Complexes with Enhanced Activity as Recyclable Single-Site Catalysts for Hydrogenation of CO2 to Methanol

Considering the importance of the valorization of CO2, a number of phosphine-containing ruthenium pincer complexes have been successfully heterogenized using a "direct knitting" strategy without any premodification. The resulting porous organometallic polymers (POMPs) with high specific-surface areas, hierarchical pores, and uniformly dispersed Ru single-sites exhibited outstanding catalytic activity toward the N-formylation of diverse amines with CO2. Besides excellent turnover number (TON, 5 x 10(5)) and turnover frequency (TOF, 5592 h(-1)), the obtained formamides were readily hydrogenated to methanol with the same catalyst. Consequently, an amine-assisted direct hydrogenation system of CO2 to methanol was established by POMPs with higher activity and TON (1.46 x (10)(4)) than their molecular precursors, shedding light on the direct valorization of CO2 and carbon neutral recycling.