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Transformation of Carbon Dioxide

“…Because inorganic carbonates such as K 2 CO 3 are used as a base in these reactions, it is possible that the CO 3 moiety in DMC comes from K 2 CO 3 (Scheme ). Microwave irradiation significantly accelerates the reaction 16 DMC Synthesis in the Presence of Methyl Iodide

17 DMC Formation from K 2 CO 3

1 Dimethyl Carbonate Synthesis from Epoxides, Methanol, and CO 2 yearepoxide a (mmol)MeOH (mmol)catalyst (g) P CO 2 (bar)temp (°C)time (h)yield (%)ref 2001 PO (25) 200 MgO (0.5) 80 150 15 14 78 2003 EO (45) 562 KI (0.2)/K 2 CO 3 (0.2) 150 140 2 73 79 2003 PO (21) 200 Mg[smectite] (0.5) 80 150 15 34 80 2004 PEPO (1) 40 DBU (0.008) 150 150 24 97 81 2004 PO (1000) 4000 5 wt % [K 2 CO 3 −KCl/MgO] (−) 25 160 5 46 82 2004 EO (10) 40 [K 2 CO 3 −KI/ZnO] (0.25) 165 150 4 69 83 2005 PO (828) 1234 KOH/molecular sieves 4A (5) 30 (rt) 180 6 17 84 2006 SO (5) 200 Bu 4 NBr (0.04)/Bu 3 N (0.02) 150 150 8 84 85 a For the abbreviations, see section 13 of this article. …”

Heterogeneous Phase Microwave-Assisted Reactions under CO2 or CO Pressure

“…Direct synthesis of DMC from CO 2 and methanol is a very attractive reaction, not only because the product is a well-known low polluting substitutive intermediate of toxic phosgene or dimethyl sulfate, but also because CO 2 can be consumed as a greenhouse compound in this process. In 2001, the first example of this synthesis was reported as a facile method for the quick synthesis of DMC from CO 2 and methanol under MW irradiation [64] and it was compared with conventional heating. In that work, rapid MW heating resulted in higher selectivity to DMC, while conductive heating (slow heating rate) may favour the formation of DMC.…”

Gaseous Reactants in Microwave‐Assisted Synthesis

“…All of them have been realized under microwave-assisted reaction conditions. The synthesis of DMC from CO 2 and MeOH was achieved by Chun et al using pulsed microwave radiation of the reaction mixture enclosed in a Pyrex tube pressurized with 0.1 MPa CO 2 [41]. MeOH was used as solvent and addition of K 2 CO 3 and MeI was necessary for acceptable conversion and DMC yield.…”