359-13-7Relevant articles and documents
In situ generation of difluoromethyl diazomethane for [3+2] cycloadditions with alkynes
Mykhailiuk, Pavel K.
, p. 6558 - 6561 (2015)
A novel approach to agrochemically important difluoromethyl-substituted pyrazoles has been developed based on the elusive reagent CF2HCHN2, which was synthesized (generated in situ) for the first time and employed in [3+2] cycloaddition reactions with alkynes. The reaction is extremely practical as it is a one-pot process, does not require a catalyst or the isolation of the potentially toxic and explosive gaseous intermediate, and proceeds in a common solvent, namely chloroform, in air. The reaction is also scalable and allows for the preparation of the target pyrazoles on gram scale. A new reagent: The elusive chemical reagent CF2HCHN2 was generated in situ for the first time and further reacted with alkynes in a [3+2] cycloaddition reaction. This transformation constitutes a novel and efficient approach to agrochemically important difluoromethylated pyrazoles.
Gas phase hydrogenolysis of methyl difluoroacetate to 1,1-difluoroethanol over Ru/C catalysts
Zheng, Su-Zhen,Cao, Xiao-Yan,Zhou, Qiang,Wang, Shu-Hua,Hu, Geng-Shen,Lu, Ji-Qing,Luo, Meng-Fei,Wang, Yue-Juan
, p. 132 - 135 (2013)
Ru/C catalysts were prepared by an impregnation method and their catalytic properties were tested for hydrogenolysis methyl difluoroacetate to difluoroethanol. The catalysts were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), CO chemisorption and H 2 temperature-programmed reduction (H2-TPR). The effects of reaction temperature, Ru content and reduction temperature of the Ru/C catalysts on the reaction were investigated. It was found that with increasing Ru contents in the Ru/C catalysts, the methyl difluoroacetate conversion, the selectivity to difluoroethanol and the TOF value first increased and then decreased. A 3Ru/C catalyst reduced at 400 °C exhibited the highest selectivity to difluoroethanol (93.5%) and the highest activity (39.5%). It was also found that the Ru/C catalyst showed a good stability of catalytic hydrogenolysis of methyl difluoroacetate within 100 h.
Method for preparing 2,2-difluoroethanol
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Paragraph 0069-0074, (2021/04/14)
The invention discloses a method for preparing 2,2-difluoroethanol. The method for preparing 2,2-difluoroethanol comprises the following steps: step (i): performing transesterification on 2,2-difluoroethyl acetate in the presence of ethanol and optionally a base.
Engineering Catalysts for Selective Ester Hydrogenation
Dub, Pavel A.,Batrice, Rami J.,Gordon, John C.,Scott, Brian L.,Minko, Yury,Schmidt, Jurgen G.,Williams, Robert F.
, p. 415 - 442 (2020/03/04)
The development of efficient catalysts and processes for synthesizing functionalized (olefinic and/or chiral) primary alcohols and fluoral hemiacetals is currently needed. These are valuable building blocks for pharmaceuticals, agrochemicals, perfumes, and so forth. From an economic standpoint, bench-stable Takasago Int. Corp.'s Ru-PNP, more commonly known as Ru-MACHO, and Gusev's Ru-SNS complexes are arguably the most appealing molecular catalysts to access primary alcohols from esters and H2 (Waser, M. et al. Org. Proc. Res. Dev. 2018, 22, 862). This work introduces economically competitive Ru-SNP(O)z complexes (z = 0, 1), which combine key structural elements of both of these catalysts. In particular, the incorporation of SNP heteroatoms into the ligand skeleton was found to be crucial for the design of a more product-selective catalyst in the synthesis of fluoral hemiacetals under kinetically controlled conditions. Based on experimental observations and computational analysis, this paper further extends the current state-of-the-art understanding of the accelerative role of KO-t-C4H9 in ester hydrogenation. It attempts to explain why a maximum turnover is seen to occur starting at 25 mol % base, in contrast to only 10 mol % with ketones as substrates.
Diaminodiphosphine tetradentate ligand and ruthenium complex thereof, and preparation methods and applications of ligand and complex
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Paragraph 0312-0315, (2019/11/04)
The invention discloses a diaminodiphosphine tetradentate ligand and a ruthenium complex thereof, and preparation methods and applications of the ligand and the complex, and provides a ruthenium complex represented by a formula I, wherein L is a diaminodiphosphine tetradentate ligand represented by a formula II, and X and Y are respectively and independently chlorine ion, bromine ion, iodine ion,hydrogen negative ion or BH4. According to the present invention, the ruthenium complex exhibits excellent catalytic activity in the catalytic hydrogenation reactions of ester compounds, has high yield and high chemical selectivity, is compatible with conjugated and non-conjugated carbon-carbon double bond, carbon-carbon triple bond, epoxy, halogen, carbonyl and other functional groups, and hasgreat application prospects.