Combining Low-Pressure CO₂ Capture and Hydrogenation To Form Methanol

Abstract

This paper describes a novel approach to CO2 hydrogenation, in which CO2 capture with aminoethanols at low pressure is coupled with hydrogenation of the captured product, oxazolidinone, directly to MeOH. In particular, (2-methylamino)­ethanol or valinol captures CO2 at 1–3 bar in the presence of catalytic Cs2CO3 to give the corresponding oxazolidinones in up to 65–70 and 90–95% yields, respectively. Efficient hydrogenation of oxazolidinones was achieved using PNN pincer Ru catalysts to give the corresponding aminoethanol (up to 95–100% yield) and MeOH (up to 78–92% yield). We also have shown that both CO2 capture and oxazolidinone hydrogenation can be performed in the same reaction mixture using a simple protocol that avoids intermediate isolation or purification steps. For example, CO2 can be captured by valinol at 1 bar with Cs2CO3 catalyst followed by 4-isopropyl-2-oxazolidinone hydrogenation in the presence of a bipy-based pincer Ru catalyst to produce MeOH in 50% yield after two steps.

Catalytic Disproportionation of Formic Acid to Methanol by an Iridium Complex Immobilized on Bipyridine‐Periodic Mesoporous Organosilica

“…The conventional hydrogenation of carbon dioxide (CO 2 ) to produce MeOH requires energy-intensive conditions such as high temperature (200-250°C) and high pressure (5)(6)(7)(8)(9)(10). The conventional hydrogenation of carbon dioxide (CO 2 ) to produce MeOH requires energy-intensive conditions such as high temperature (200-250°C) and high pressure (5)(6)(7)(8)(9)(10).…”

“…[2] However, there were problems in improving the catalysis for hydrogenation of CO 2 to FA and subsequent hydrogenation of FA to MeOH. Therefore, the indirect hydrogenation of CO 2 to MeOH has been investigated by using CO 2 derivatives such as carbonate [4] , carbamate [5] , formate [6] , and urea [7] . Therefore, the indirect hydrogenation of CO 2 to MeOH has been investigated by using CO 2 derivatives such as carbonate [4] , carbamate [5] , formate [6] , and urea [7] .…”

Manganese Catalyzed Hydrogenation of Organic Carbonates to Methanol and Alcohols

“…[3] In particular, hydrogenation of organic carbonates is ad esirable reaction because of its relevance to the indirect synthesis of methanol, av ersatile chemical and ap otential fuel, from CO 2 ,awaste product and greenhouse gas (Scheme 1). [6] Ding also reported ruthenium catalyzed hydrogenation of cyclic carbonates to methanol and diols. [4] Af ew years ago,w ereported the first catalytic hydrogenation of organic carbonates and carbamates,w hich are readily available from CO 2 ,t om ethanol and alcohols using ruthenium pincer catalysts,t hus providing am ild, low pressure two-step process for the conversion of CO 2 to methanol.…”

“…Under the same catalytic conditions,hydrogenation of diethyl carbonate resulted in the formation of ethanol and methanol in 97 %a nd 95 %y ields,r espectively.D ibenzyl carbonate, diphenyl carbonate,a nd unsymmetrical methyl carbonates ( Table 1, entries [5][6][7][8][9][10][11] were also hydrogenated to afford the corresponding alcohol and methanol in good to excellent yields.W ethen used complex 1 for the hydrogenation of the more challenging cyclic carbonates.U nder the optimized conditions used for the hydrogenation of acyclic carbonates, only 60 %c onversion of propylene carbonate was observed, forming propylene glycol and methanol in % 60 %a nd 45 % yields,r espectively.I ncreasing the hydrogen pressure to 50 bar and reaction time to 48 hr esulted in the quantitative conversion of propylene carbonate to propylene glycol and methanol. Increasing the reaction time to 30 hand the amount of base to 4mol %resulted in approximately quantitative conversion of dimethyl carbonate to methanol, which was detected in 90 % yield by 1 HNMR spectroscopy.Encouraged by this result, we explored the hydrogenation of other types of carbonates.…”

Metall‐Ligand‐Kooperation

“…Da diese Verbindungen aus CO 2 oder CO gebildet werden können, bietet diese Reaktion einen milden, zweistufigen Prozess für die Hydrierung dieser Gase zu Methanol. Tatsächlich führte dies zur Entwicklung einer zweistufigen Prozedur für den CO 2 ‐Einfang mit Aminoalkoholen bei niedrigem Druck gefolgt von der Hydrierung der in situ gebildeten Oxazolidinone zu MeOH 100…”