375-02-0Relevant articles and documents
Study of fluorocarbonyls for the Baylis-Hillman reaction
Venkat,Reddy, Ram,Rudd, Michael T.,Ramachandran, P. Veeraraghavan
, p. 5382 - 5385 (2002)
A study of the effect of fluorine substitution in Baylis-Hillman reactions of various fluorocarbonyl partners with acrolein, methyl vinyl ketone, ethyl acrylate, and acrylonitrile has been made.
The gas phase tropospheric removal of fluoroaldehydes (CxF 2x+1CHO, x = 3, 4, 6)
Solignac,Mellouki,Le Bras,Yujing, Mu,Sidebottom
, p. 4200 - 4210 (2007)
The rate coefficient of the OH reaction with the perfluoroaldehydes C 3F7CHO and C4F9CHO have been determined in the temperature range 252-373 K using the pulsed laser photolysis-laser induced fluorescence (PLP-LIF) method: kC3F7CHO+OH = (2.0 ± 0.6) × 10-12 exp[-(369 ± 90)/T] and kC4F9CHO+OH = (2.0 ± 0.5) × 10-12 exp[-(356 ± 70)/T] cm3 molecule-1 s-1, corresponding to (5.8 ± 0.6) × 10-13 and (6.1 ± 0.5) × 10-13 cm3 molecule-1 s -1, respectively, at 298 K. The UV absorption cross sections of these two aldehydes and CF3(CF2)5CH2CHO have been measured over the range 230-390 nm at 298 K and also at 328 K for CF3(CF2)5CH2CHO. The obtained results for C3F7CHO and C4F9CHO are in good agreement with two recent determinations but the maximum value of the absorption cross section for CF3(CF2)5CH 2CHO is over a factor of two lower than the single one recently published. The photolysis rates of C3F7CHO, C 4F9CHO and CF3(CF2)5CHO have been measured under sunlight conditions in the EUPHORE simulation chamber in Valencia (Spain) at the beginning of June. The photolysis rates were, respectively, Jobs = (1.3 ± 0.6) × 10-5, (1.9 ± 0.8) × 10-5 and (0.6 ± 0.3) × 10 -5 s-1. From the Jobs measurements and calculated photolysis rate Jcalc, assuming a quantum yield of unity across the atmospheric range of absorption of the aldehydes, quantum yields Jobs/Jcalc = (0.023 ± 0.012), (0.029 ± 0.015) and (0.046 ± 0.028) were derived for the photodissociation of C3F7CHO, C4F9CHO and CF 3(CF2)5CHO, respectively. The atmospheric implication of the data obtained in this work is discussed. The main conclusion is that the major atmospheric removal pathway for fluoroaldehydes will be photolysis, which under low NOx conditions, may be a source of fluorinated carboxylic acids in the troposphere. the Owner Societies.
Atmospheric chemistry of fluorinated alcohols: Reaction with Cl atoms and OH radicals and atmospheric lifetimes
Hurley,Wallington,Sulbaek Andersen,Ellis,Martin,Mabury
, p. 1973 - 1979 (2004)
Relative rate techniques were used to study the kinetics of the reactions of Cl atoms and OH radicals with a series of fluorinated alcohols, F(CF2)nCH2OH (n = 1-4), in 700 Torr of N2 or air diluent at 296 ± 2 K. The length of the F(CF2)n group had no discernible impact on the reactivity of the molecule. For n = 1-4, k(Cl + F(CF2)nCH2OH) = (6.48 ± 0.53) × 10-13 and k(OH + F(CF2)nCH2OH) = (1.02 ± 0.10) × 10-13 cm3 molecule-1 s-1. Product studies of the chlorine initiated oxidation of F(CF2)nCH2OH (n = 1-4) in the absence of NO show the sole primary product to be the corresponding aldehyde, F(CF2)nC(O)H. Consideration of the likely rates of other possible atmospheric loss mechanisms leads to the conclusion that the atmospheric lifetime of F(CF2)nCH2OH (n ≥ 1) is determined by reaction with OH radicals and is approximately 164 days.
