85213-04-3

Upstream product

• 78-83-1 2-methyl-propan-1-ol 
• 79-22-1 methyl chloroformate 
• 67-56-1 methanol 
• 543-27-1 isobutyl chloroformate 
• 616-38-6 carbonic acid dimethyl ester 
• 124-38-9 carbon dioxide 
• 74-88-4 methyl iodide 

Relevant academic research and scientific papers

Room temperature and normal pressure preparation method of organic carbonate

The invention relates to the technical field of organic synthesis, and provides a room temperature and normal pressure preparation method of organic carbonate. The method comprises the following steps: introducing carbon dioxide into an imidazole ionic liquid to obtain a mixture; mixing the obtained mixture with alcohol and halogenated hydrocarbon, and carrying out addition-substitution reactionsto obtain organic carbonate. The whole reaction process is carried out at a room temperature under a normal pressure. The activation energy of the reaction is reduced by using imidazole ionic liquid and halogenated hydrocarbon, and finally, organic carbonate is prepared from CO2 at a room temperature under a normal pressure.

Synthesis of non-symmetrical alkyl carbonates from alcohols and DMC over the nanocrystalline ZSM-5 zeolite

A novel heterogeneous acid (nanocrystalline ZSM-5) catalyzed carboxymethylation of alcohols to non-symmetrical alkyl carbonates using DMC has been realized. Nanocrystalline ZSM-5 (NZSM-5) with a crystal size of 20-30 nm was synthesized by hydrothermal crystallization. The synthesized NZSM-5 was verified by X-ray diffraction, Fourier transformation infrared spectroscopy and solid state NMR. The morphology of NZSM-5 was confirmed by transmission electron microscopy and scanning electron microscopy, which revealed the formation of aggregates of the zeolite (100-200 nm) made by the nano-sized (20-30 nm) NZSM-5 particle packing. The physicochemical properties of NZSM-5 were measured by nitrogen adsorption and temperature programmed desorption of ammonia, which indicate the surface area of 465 m2 g-1 and the acidity of 0.936 mmol g-1. The present protocol provides an attractive approach to a variety of non-symmetrical alkyl carbonates in high yields. The catalyst was efficiently recycled for up to 5 consecutive cycles. This method broadens the series of possible utilization for DMC in green chemistry.

Asymmetric organic carbonate synthesis catalyzed by an enzyme with dimethyl carbonate: A fruitful sustainable alliance

We have successfully developed an easy and efficient bioprocess for asymmetric organic carbonate synthesis by performing Novozym 435 mediated esterification of DMC and alcohols in this work. Under the optimized conditions (60 °C, molar ratio of alcohol to DMC 1:12), the highest yield of carbonate can reach 95.6%. An additional advantage of the new process is the fact that 90% of the original activity of the enzyme is retained after being recycled nine times. Consequently it has potential as a useful enzyme-catalyzed process for the industrial production of asymmetric organic carbonates. The Royal Society of Chemistry 2014.

Kinetic evaluation of the solvolysis of isobutyl chloro-and chlorothioformate esters

The specific rates of solvolysis of isobutyl chloroformate (1) are reported at 40.0 °C and those for isobutyl chlorothioformate (2) are reported at 25.0 °C, in a variety of pure and binary aqueous organic mixtures with wide ranging nucleophilicity and ionizing power. For 1, we also report the first-order rate constants determined at different temperatures in pure ethanol (EtOH), methanol (MeOH), 80% EtOH, and in both 97% and 70% 2,2,2- trifluoroethanol (TFE). The enthalpy ΔH≠ and entropy ΔS≠ of activation values obtained from Arrhenius plots for 1 in these five solvents are reported. The specific rates of solvolysis were analyzed using the extended Grunwald-Winstein equation. Results obtained from correlation analysis using this linear free energy relationship (LFER) reinforce our previous suggestion that side-by-side addition-elimination and ionization mechanisms operate, and the relative importance is dependent on the type of chloro-or chlorothioformate substrate and the solvent.

METHOD OF PREPARING DIALKYLCARBONATES

The present invention relates to a process of preparing dialkylcarbonates, and particularly to an improved process of preparing dialkylcarbonates, which comprises performing a reaction between an alcohol compound and a chloroformate derivative in the presence of an imidazole compound, thereby enabling to prepare dialkylcarbonates with high yield in a mild condition without using toxic raw materials and to easily separate impurities.

KINETICS OF SOLVOLYSIS OF ALKYL CHLOROFORMATES IN ALIPHATIC ALCOHOLS

The kinetics of the solvolysis of methyl and 2,2,3,3-tetrafluoropropyl chloroformate in aliphatic alcohols were investigated.The sensitivity to change in the structure of the alcohol decreases with increase in the reactivity of the chloroformate, and this is consistent with the selectivity principle.The effect of the structure of the substituent in the alcohol and the activation parameters confirm the addition-elimination mechanism.