149-73-5Relevant articles and documents
A PRIMARY KINETIC ISOTOPE EFFECT FOR THE O-H INSERTION OF DIMETHOXYCARBENE
Moss, Robert A.,Shen, Shilan,Wlostowski, Marek
, p. 6417 - 6420 (1988)
The primary kinetic isotope effect for the insertion of dimethoxycarbene into MeOH(D) is 3.3 +/- o.5.
Selective production of difluoromethyl methyl ether from chlorodifluoromethane using alkali metal carbonates
Lee,Hoon Sik Kim,Sang Deuk Lee,Won Koo Lee,Kim
, p. 133 - 136 (2001)
CHF2OCH3 (HFE-152a), an important starting material for synthesizing various C2 hydrofluoroethers and a prospective alternative to CH3CF2Cl (HCFC-142b), has been found to be effectively produced from the reaction of CHF2Cl (HCFC-22) with alkali metal carbonates in methanol. Some alkali metal carbonates induce selective production of CHF2OCH3 with a small amount of CH(OCH3)3, a major side product. Activities of alkali metal carbonates for producing CHF2OCH3 are in the order of K2CO3 > Na2CO3 > Li2CO3, suggesting that the solubility and ionization tendency of alkali metal carbonate in methanol play important roles in the reaction.
Reactions of dimethoxycarbene and fluoromethoxycarbene with hydroxyl compounds. Absolute rate constants and the heat of formation of dimethoxycarbene
Du,Fan,Goodman,Kesselmayer,Krogh-Jespersen,LaVilla,Moss,Shen,Sheridan
, p. 1920 - 1926 (1990)
Dimethoxycarbene [(MeO)2C] and fluoromethoxycarbene (FCOMe) were photochemically generated from the appropriate diazirines (2a and 2b) and characterized by UV and IR spectroscopy in cold matrices and by UV in solution at 20-25°C. Laser flash photolytic studies determined rate constants for the reactions of the carbenes with ethanol, methanol, chloroethanol, fluoroethanol, trifluoroethanol, hexafluoroisopropyl alcohol, and acetic acid. The reactivity of (MeO)2C with the alcohols spanned 4 orders of magnitude, with kψ for carbene decay in 1 M ROH/CH3CN ranging from 3.2 X 104 S-1 (ethanol) to 6.7 X 108 S-1 (hexafluoroisopropyl alcohol). A Bronsted correlation (α = 0.66) was obtained between log kψ for the decay of (MeO)2C in 1 M ROH/CH3CN and the pK(a) of ROH (in water). FCOMe was much less reactive toward ROH than (MeO)2C; only with hexafluoroisopropyl alcohol (kψ ~9 X 103 s-1 for carbene decay in 1 M ROH/CH3CN) could quenching be observed. Products of some of the carbene/alcohol reactions were characterized. A photoacoustic calorimetry study of the (MeO)2/MeOH reaction afforded ΔH(f) ~ -61 kcal/mol for (MeO)2C;ΔH(f) for FCOMe was estimated at ~ -53 to -56 kcal/mol. The mechanism(s) of the carbene/O-H insertion reactions are discussed. The results of ab initio and semiempirical molecular orbital calculations on FCOMe are presented.
Synthesis method of crude carboxylic ester (by machine translation)
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Paragraph 0021; 0022, (2020/08/09)
The method is characterized in that the carboxylic ester and the ether are prepared by reacting a carboxylic ester with an ether at a certain temperature under the catalysis of a catalyst at a certain pressure for a certain time. (by machine translation)
Green preparing orthoformate cleaning process
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Paragraph 0038; 0040; 0041, (2016/10/07)
The invention provides a green process for preparing orthoformate. A hydrogen chloride alcohol solution is prepared from a byproduct hydrogen chloride tail gas of the chlorine-related synthesis industry and then is slowly added into a reaction system, so that loss caused by escape of hydrocyanic acid is reduced, the yield is increased, great equipment corrosion caused by the byproduct hydrochloric acid prepared by the companies is avoided, the economic additional value of the byproduct hydrogen chloride is greatly increased, three wastes are avoided, the byproduct only comprises ammonium chloride, resources are reasonably utilized, and the green process for preparing the orthoformate is an environment-friendly production process and has a good social benefit.
