35466-86-5Relevant academic research and scientific papers
PRODUCTION METHOD OF ASYMMETRIC CHAIN CARBONATE
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Paragraph 0125; 0131; 0137, (2019/01/04)
A method for producing an asymmetric chain carbonate by reacting an alcohol with a halocarbonate ester compound in the presence of a basic magnesium salt.
Selective N,N-dimethylation of primary aromatic amines with methyl alkyl carbonates in the presence of phosphonium salts
Selva, Maurizio,Perosa, Alvise,Tundo, Pietro,Brunelli, Davide
, p. 5770 - 5773 (2007/10/03)
In the presence of onium salts, at 140-170 °C. methyl alkyl carbonates [1a-c, ROCO2Me, R = MeO(CH2)2[O(CH 2)2]n; n = 2-0, respectively] react with primary aromatic amines (XC6H4NH2, X = p-OMe, p-Me, H, p-Cl, p-CO2Me, o-Et, and 2,3-Me2C 6H3NH2) to yield the corresponding N,N-dimethyl derivatives (ArNMe2) with high selectivity (up to 96%) and good isolated yields (78-95%). Phosphonium salts (e.g., Ph3PEtI and n-Bu4PBr) are particularly efficient catalysts. Overall, a solvent-free reaction is coupled with safe methylating agents (1a-c) made from nontoxic dimethyl carbonate.
PROCESS FOR PRODUCING DIALKYL CARBONATE AND DIOL
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Page/Page column 26-29, (2010/02/15)
A process for producing a dialkyl carbonate and a diol, comprising (a) subjecting a cyclic carbonate and an aliphatic monohydric alcohol to transesterification in the presence of a transesterification catalyst to produce a reaction solution containing a dialkyl carbonate and a diol, (b) extracting a dialkyl carbonate-containing reaction solution from the reaction solution and then separating a dialkyl carbonate from the dialkyl carbonate-containing reaction solution, and (c) extracting a diol-containing reaction solution from the reaction solution and then separating a diol from the diol-containing reaction solution. This process is characterized in that the content of a cyclic ether in the cyclic carbonate is 0.1 to 3,000 ppm and the content of carbonate ether in the dialkyl carbonate thus obtained is not more than 10,000 ppm.
Mechanism and structure-reactivity correlation in the homogeneous, unimolecular elimination kinetics of 2-substituted ethyl methylcarbonates in the gas phase
Chuchani, Gabriel,Marquez, Edgar,Herize, Armando,Dominguez, Rosa Maria,Tosta, Maria,Brusco, Doris
, p. 839 - 848 (2007/10/03)
The gas-phase elimination kinetics of 2-substituted ethyl methylcarbonates were determined in a static reaction system over the temperature range of 323-435 °C and pressure range 28.5-242 Torr. The reactions are homogeneous, unimolecular and follow a first-order rate law. The kinetic and thermodynamic parameters are reported. The 2-substituents of the ethyl methylcarbonate (CH3OCOOCH2CH2Z, Z = substituent) give an approximate linear correlation when using the Taft-Topsom method, log(k z/kH)= -(0.57 ± 0.19)σα + (1.34 ± 0.49)σR (r = 0.9256; SD = 0.16) at 400 °C. This result implies the elimination process to be sensitive to steric factors, while the electronic effect is unimportant. However, the resonance factor has the greatest influence for a favorable abstraction of the β-hydrogen of the C3- H bond by the oxygen carbonyl. Because ρα is significant, a good correlation of the alkyl substituents of carbonates with Hancock's steric parameters was obtained: log(kR/kH versus Esc for CH 3OCOOCH2CH2R at 400°C, R = alkyl, δ= -0.17 (r=0.9993, SD = 0.01). An approximate straight line was obtained on plotting these data with the reported Hancock's correlation of 2-alkyl ethylacetates. This result leads to evidence for the β-hydrogen abstraction by the oxygen carbonyl and not by the alkoxy oxygen at the opposite side of the carbonate. The carbonate decompostion is best described in terms of a concerted six-membered cyclic transition state type of mechanism. Copyright
