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).
Novel preparation method of 3, 3, 3-trifluoropropionic acid
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Paragraph 0025; 0026; 0029; 0030; 0033-0034; 0037-0038; 0040, (2020/04/02)
The invention discloses a novel preparation method of 3, 3, 3-trifluoropropionic acid, and relates to the field of medical pesticides. 1, 1-dichloroethylene is used as a raw material to be subjected to an addition reaction with chloroformate or ester under the catalysis of iron powder to obtain trichloropropionate or salt thereof, the trichloropropionate or salt thereof is smoothly subjected to afluorination reaction under proper conditions to efficiently obtain trifluoropropionate or fluorine trifluoropropionate, and the trifluoropropionate or fluorine trifluoropropionate is hydrolyzed to obtain 3, 3, 3-trifluoropropionic acid. In conclusion, the method for preparing trifluoropropionic acid has the advantages of cheap and easily available initial raw materials, simple reaction operation,mild reaction conditions, few steps and high conversion rate, and the conversion rate of the raw material 1, 1-dichloroethylene exceeds 78%.
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.