Dimethyl carbonate synthesis

Yun-Jin Fang and Wen-De Xiao, Experimental and modeling studies on a homogeneous reactive distillation system for dimethyl carbonate synthesis by transesterification, Separation and purification technology, 34 (2004) 255. 

Yang Z-Z, He L-N, Dou X-Y et al (2010) Dimethyl carbonate synthesis catalyzed by DABCO-derived basic ionic liquids via transesterification of ethylene carbonate with methanol. Tetrahedron Lett 51(21) 2931-2934... 

Bhanage BM, Fujita S-i, Ikushima Y (2003) Transesterification of urea and ethylene glycol to ethylene carbonate as an important step for urea based dimethyl carbonate synthesis. Green Chem 5(4) 429-432... 

Yang Z-Z, Dou X-Y, Wu F et al (2011) NaZSM-5-catalyzed dimethyl carbonate synthesis via the transesterification of ethylene carbonate with methanol. Can J Chem 89(5) 544-548... 

Tomishige, K. Sakaihori, T. Sakai, S.-I. Fujimoto, K. Dimethyl carbonate synthesis by oxidative carbonylation on activated carbon supported CUCI2 catalysts catalytic properties and structural change. Appl. Catal. A. 1999,181, 95-102. 

Mesoporous solid base catalyst was prepared by loading KI, K2CO3 and KOH on mesoporous active carbon and was used to catalyze dimethyl carbonate synthesis from propylene carbonate and methanol. The effect of preparation method, base strength, catalyst content, reaction time and ten erature were investigated. 

In the palladium-alkyl nitrite system, the gas phase synthesis of diallqrl carbonates has mainly been studied and not many examples are known concerning the liquid phase variants. For catalyst supports, alumina, activated carbon.f and Li-Al-0(spinel)f were successfully utilized in dimethyl carbonate synthesis (Table 4). 

Otsuka K, Yagj T, Yamanaka I (1994) Dimethyl carbonate synthesis by electrolytic carhonylation of methanol in the gas phase. Eleclrochim Acta 39 2109-2115... 

Ballivet-Tkatchenko D, Douteau O, Stutzmann S (2000) Reactivity of carbon dioxide with n-butyl(phenoxy)-, (alkoxy)-, and (oxo)stararanes insight into dimethyl carbonate synthesis. Organomet 19 4563-4567... 

Kohno K, Choi J-C, Ohshima Y, Yili A, Yasuda H, Sakakura T (2008) Reaction of dibutyltin oxide with methanol under CO2 pressure relevant to catalytic dimethyl carbonate synthesis. J Organomet Chem 693 1389-1392... 

Ikeda Y, Asadullah M, Fujimoto K, Tomishige K (2001) Structure of the active sites on Fl3P04/Zr02 catalysts for dimethyl carbonate synthesis from methanol and carbon dioxide. 

Jung KT, Bell AT (2001) An in situ infrared study of dimethyl carbonate synthesis from carbon dioxide and methanol over zirconia. J Catal 204 339-347... 

Eta V, Maki-Arvela P, Wama J, Salmi T, Mikkola J-P, Murzin DY (2011) Kinetics of dimethyl carbonate synthesis from methanol and carbon dioxide over Zi02-MgO catalyst in the presence of butylene oxide as additive. Appl Catal A Gen 404 39-46... 

Cheong M, Kim S-C, Park JB (1997) Dimethyl carbonate synthesis via carbon dioxide activation in the presence of iodide catalysts. New J Chem 21 1143-1145... 

Gaoa Y, Penga W, Zhaoa N, Wei W, Sun Y (2011) A DFT study on the reaction mechanism for dimethyl carbonate synthesis from methyl carbamate and methanol. J Mol Catal A Chem 35 29 0... 

As was reported by Romano et aL, cuprous chloride is an effective catalyst for selective dimethyl carbonate synthesis. The reaction proceeds at 90—100 C at >20 bar of CO and can be either separated into an oxidation and a reduction step, or carried out in a one-pot redox system [71]. Dimethyl carbonate is a versatile reagent which can replace phosgene and dimethyl sulfate as carbonylating and methylating agents, respectively. 

SCHEME 5.2 Dimethyl carbonate synthesis from methanol and CO. ... 

SCHEME 5.3 Dimethyl carbonate synthesis from EO/PO, CO and methanol. 

Keller, N. Rebmann, G. Keller, V. Catalysts, Mechanisms and Industrial Processes for the Dimethyl Carbonate Synthesis. J. Mol. Catal. A Chem. 2010, 317,1-18. 

Xei, S. Bell, A.T. An Raman Study of Dimethyl Carbonate Synthesis from Carbon Dioxide and Methanol over Ziieonia. Catal. Lett. 2000,70,137-143. 

Ikeda, Y Asadullah, M. Fujimoto, K. Tomishige, K. Structure of the Active Sites on HjPO/ZrOj Catalysts for Dimethyl Carbonate Synthesis from Methanol and Carbon Dioxide. J. Phys. Chem. B 2001,105,10653-10658. 

Oxygenates and Chemicals A whole host of oxygenated products, i.e., fuels, fuel additives, and chemicals, can be produced from synthesis gas. These include such produc ts as methanol, ethylene, isobutanol, dimethyl ether, dimethyl carbonate, and many other hydrocarbons and oxyhydrocarbons. Typical oxygenate-producing reactions are ... 

Dimethyl carbonate (DMC) is a colorless liquid with a pleasant odor. It is soluble in most organic solvents but insoluble in water. The classical synthesis of DMC is the reaction of methanol with phosgene. Because phosgene is toxic, a non-phosgene-route may be preferred. The new route reacts methanol with urea over a tin catalyst. However, the yield is low. Using electron donor solvents such as trimethylene glycol dimethyl ether and continually distilling off the product increases the yield. ... 

Synthesis of dimethyl carbonate by transesterification of ethylene carbonate and methanol using quaternary ammonium salt catalysts... 

Hydroxymethylation (formaldehyde) of nitro-imidazole 76 affords 77, which is oxidized to aldehyde 78. To prepare the other fragment for this convergent synthesis, reaction of epichlorohydrin with morpholine leads to the aminoepoxide 79, which is reacted with hydrazine to afford 80. Reaction of this substituted hydrazine with dimethyl carbonate affords oxazolinone 81 by sequential ester interchange reactions. Condensation of 81 with aldehyde 78 affords the antitricho-... 

The oxidative carbonylation of alcohols and phenols to carbonates can be catalyzed by palladium or copper species [154-213]. This reaction is of particular practical importance, since it can be developed into an industrial process for the phosgene-free synthesis of dimethyl carbonate (DMC) and diphenyl carbonate (DPC), which are important industrial intermediates for the production of polycarbonates. Moreover, DMC can be used as an eco-friendly methylation and carbonylation agent [214,215]. The industrial production of DMC by oxidative carbonylation of methanol has been achieved by Enichem [216] and Ube [217]. 

Tundo and colleagues reported the synthesis of 4-oxazolin-2-one 110 by [3,3]-sigmatropic rearrangement of an enehydroxylamine derivative 109 resulting from the reaction of a ketoxime with dimethyl carbonate at high temperatures and in basic medium (equation 33). 

The reaction of dimethyl carbonate with synthesis gas requires a cobalt-iodide catalyst and operating conditions of 180 C and 4000 psig. The acetaldehyde rate approaches 30 M/hr with selectivities greater than 85%. The productivities are much better than with methanol however, recycle of the CO and methanol back to dimethyl carbonate is very difficult ... 

Dimethyl carbonate is an interesting material which can be used instead of toxic dimethyl sulfate as a multipurpose alkylating reagent.438-578 Its synthesis can be performed in one step from cheap methanol, CO and oxygen materials in the presence of copper salts (e.g. copper(ll) methoxychloride or CuCl/py) at ca. 100 °C and 15-70 atm (equation 290).578,62S This reaction is thought to proceed in two steps 578 (a) formation of copper(II) methoxychloride from the reaction of copper(I) chloride, 02 and methanol (equation 291) and (b) reduction of copper(II) methoxychloride with CO to form dimethyl carbonate and regenerate copper(I) chloride (equation 292).626... 

Scheme 6.7 Synthesis of carbamates from aliphatic primary amines and dimethyl carbonate (DMC) in the presence of C02. The catalytic role of C02.

Alkylene CCs have been prepared through the transesterification of appropriate glycols with dialkyl carbonates (usually diethyl or dimethyl carbonate) in the presence of a suitable catalyst. One of the first such examples was the synthesis of six-membered CCs by the transesterification of propane-1,3-diols with DEC catalyzed by sodium ethanolate (Equation 7.31) [289], The reaction was carried out at temperatures between 293 and 333 K, and a conversion yield of 40% was obtained. 

A significant problem in scaling up the Kolbe reaction is the long-term stability of the expensive platinum anodes. Therefore, many attempts have been made to find a a cheaper anode material. One example is the Sowjet work 226), which shows that special carbon anodes can be used. Thus, the loss of carbon in the dimethyl sebacate synthesis (yield 72.2 %) after 8,400 Ah/m2 is only 0.008 %. Monsanto121) has attempted to pair the sebacate synthesis with various cathode reactions. 

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