2516-99-6Relevant articles and documents
Peters et al.
, p. 376,377 (1971)
UV absorption cross sections between 230 and 350 nm and pressure dependence of the photolysis quantum yield at 308 nm of CF3CH2CHO
Antinolo, Maria,Jimenez, Elena,Albaladejo, Jose
, p. 15936 - 15946 (2011)
Ultraviolet (UV) absorption cross sections of CF3CH 2CHO were determined between 230 and 350 nm by gas-phase UV spectroscopy. The forbidden n → π* transition was characterized as a function of temperature (269-323 K). In addition, the photochemical degradation of CF3CH2CHO was investigated at 308 nm. The possible photolysis channels are: CF3CH2 + HCO (R1a), CF3CH3 + CO (R1b), and CF3CH2CO + H (R1c). Photolysis quantum yields of CF3CH2CHO at 308 nm, Φλ=308nm, were measured as a function of pressure (25-760 Torr of synthetic air). The pressure dependence of Φ λ=308nm can be expressed as the following Stern-Volmer equation: 1/Φλ=308nm = (4.65 ± 0.56) + (1.51 ± 0.04) × 10-18 [M] ([M] in molecule cm-3). Using the absorption cross sections and the photolysis quantum yields reported here, the photolysis rate coefficient of this fluorinated aldehyde throughout the troposphere was estimated. This calculation shows that tropospheric photolysis of CF3CH2CHO is competitive with the removal initiated by OH radicals at low altitudes, but it can be the major degradation route at higher altitudes. Photodegradation products (CO, HC(O)OH, CF 3CHO, CF3CH2OH, and F2CO) were identified and also quantified by Fourier transform infrared spectroscopy. CF3CH2C(O)OH was identified as an end-product as a result of the chemistry involving CF3CH2CO radicals formed in the OH + CF3CH2CHO reaction. In the presence of an OH-scavenger (cyclohexane), CF3CH2C(O)OH was not detected, indicating that channel (R1c) is negligible. Based on a proposed mechanism, our results provide strong evidences of the significant participation of the radical-forming channel (R1a).
Preparation method of 3, 3, 3-trifluoropropionic acid
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Paragraph 0036; 0039; 0040; 0044; 0045; 0049; 0050; 0054, (2020/05/02)
The invention discloses a preparation method of 3, 3, 3-trifluoropropionic acid. The preparation method comprises the following steps: firstly, taking 2-chloro-1-1-difluoroethylene (a) as a raw material and carrying out a carbonylation reaction between the raw material and carbon monoxide to obtain 3, 3-difluoro-2-allyl chloride (b); carrying out a fluorination reaction on 3, 3-difluoro 2-allyl chloride by using hydrogen fluoride (HF) to obtain 3, 3, 3-trifluoropropionyl fluoride (c); and finally hydrolyzing the 3, 3, 3-trifluoropropionyl fluoride to obtain trifluoropropionic acid (d). The preparation method has the advantages as follows: the raw materials are cheap and easily available; conditions are mild; conversion rate of the starting material is high; and the total yield of the three-step reactions can reach 50% or above.
A 3, 3, 3 - three fluorine propionic acid high efficient synthesis method
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Paragraph 0021-0052, (2019/03/23)
The invention discloses a 3, 3, 3 - three fluorine propionic acid preparation method, relates to pharmaceutical intermediates preparation field, specifically comprises the following steps: first preparing a walnut shells powder, and then mixed with the tetrabutyl titanate, access with water-nitrogen, reaction at certain temperature, the produced solid with the molybdate mixed sintering treatment, to obtain the catalyst, finally to 3, 3, 3 - trifluoro propionaldehyde as raw materials, in order to hydrogen peroxide as the oxidizing agent, the above mentioned catalyst under the catalysis of the reaction, to obtain the target product, 3, 3, 3 - trifluoro propionaldehyde. The method of the invention process is simple, less catalyst levels, high product yield.
