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.
Gas phase UV and IR absorption spectra of CxF2x+1CHO (x = 1-4)
Hashikawa,Kawasaki,Waterland,Hurley,Ball,Wallington,Andersen, M.P. Sulbaek,Nielsen
, p. 1925 - 1932 (2004)
The UV and IR spectra of CxF2x +1CHO (x = 1-4) were investigated using computational and experimental techniques. CxF2x+1CHO (x = 1-4) have broad UV absorption features centered at 300-310 nm. The maximum absorption cross-section increases significantly and shifts slightly to the red with increased length of the CxF2x+1 group: CF3CHO, 3.10 × 10-20 (300 nm); C 2F5CHO, 6.25 × 10-20 (308 nm); C 3F7CHO, 8.96 × 10-20 (309 nm); and C 4F9CHO, 10.9 × 10-20 (309 nm). IR spectra for CxF2x+1CHO were recorded, calculated, and assigned. Results are discussed with respect to the literature data and to the atmospheric fate of CxF2x+1CHO.
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.
Incorporation of a 3-(2,2,2-Trifluoroethyl)-γ-hydroxy-γ-lactam motif in the side chain of 4-aminoquinolines. Syntheses and antimalarial activities
Cornut, Damien,Lemoine, Hugues,Kanishchev, Oleksandr,Okada, Etsuji,Albrieux, Florian,Beavogui, Abdoul Habib,Bienvenu, Anne-Lise,Picot, Stéphane,Bouillon, Jean-Philippe,Médebielle, Maurice
, p. 73 - 83 (2013/02/23)
In this paper we report the synthesis and antimalarial properties of two series of fluoroalkylated γ-lactams derived from 4-aminoquinoline as potent chemotherapeutic agents for malaria treatment. These molecules obtained in several steps resulted in the identification of very potent structures with in vitro activity against Plasmodium falciparum clones of variable sensitivity (3D7 and W2) in the range of 19-50 nM with resistance indices in the range of 1.0-2.5. In addition, selected molecules (50, 51, 58, 60, 63, 70, 72, 74, 78, 81, 84, and 87) that are representative of the two series of compounds did not show cytotoxicity in vitro when tested against human umbilical vein endothelial cells up to a concentration of 100 μM. The most promising compounds (82 and 84) showed significant IC50 values close to 26 and 19 nM against the chloroquino-sensitive strain 3D7 and 49 and 42 nM against the multi-drug-resistant strain W2. Furthermore, two model compounds (50 and 70) were found to be quite stable over 48 h at pH 7.4 and 5.2. Overall, our preliminary data indicate that this class of structures contains promising candidates for further study.
Fluorine Substituent Effects on Alkoxide Chemistry and Orientation on the Cu(100) Surface
Dai, Qing,Gellman, Andrew J.
, p. 10783 - 10789 (2007/10/02)
The straight chain hydrocarbon alcohols (CH3(CH2)nOH, n = 0-4) and fluorocarbon alcohols (CF3(CF2)nCH2OH, n = 0-2) all adsorb reversibly on the clean Cu(100) surface.As the alkyl chain is lengthened, the heats of adsorption of the hydrocarbon alcohols are incremented by 1.2 kcal/mol per CH2 group while the heats of adsorption of the fluorinated alcohols are incremented by 0.7 kcal/mol per CF2 group.On the preoxidized Cu(100) surface the alcohols are all deprotonated to form alkoxides.The intensity of the νCO mode in the HREEL spectra suggests that the C-O bond lies along the surface normal in methoxide and the propoxides but is ted toward the surface in ethoxides, butoxides, and pentoxide.During heating the alkoxides decompose by β-hydride elimination to yield aldehydes.Fluorination of the alkyl chain in the Γ-position has a dramatic influence on the reaction kinetics, resulting in an increase in the β-hydride elimination barrier from 26 kcal/mol in hydrocarbon alkoxides to 42 kcal/mol in the fluorinated alkoxides.This is consistent with a description of the transition state in which charge separation is of the form Cβδ+Hδ- and the influence of the fluoroalkyl group is to energetically destabilize the cationic β-carbon in the transition state.
Heterocyclic Polyfluoro-compounds. Part 31. Photochemical Oxetan Formation from Fluoroketones and Perfluoroaldehydes and 1,2-Difluoroethylene
Barlow, Michael G.,Coles, Barrie,Haszeldine, Robert N.
, p. 2258 - 2267 (2007/10/02)
The photochemical addition of five fluoroketones (hexafluoro-, chloropentafluoro-, 1,3-dichlorotetrafluoro-, 1,1,3-trichlorotrifluoro-, and 1,1,1-trifluoro-propan-2-one) and the perfluoroaldehydes RFCHO (RF=CF3, C2F5, or n-C3F7) to (Z)- or (E)-1,2-difluoroethylene at λ > 300 nm has been studied.Oxetan formation dominates with hexafluoropropan-2-one, but there is increasing competition from reactions involving free radicals arising from photolysis of the ketone as the chlorine content is increased.Oxetan formation occurs with little stereospecificity.The aldehydes give r-2-perfluoroalkyl-t-3,c-4-, and -c-3,t-4-, and -t-3,t-4-difluoro-oxetans, in the ratio 1.0 : 1.7 +/- 0.2 : 1.3 +/- 0.1, respectively, and in high yield (78-94percent).A small amount of olefin isomerisation occurred. Flow pyrolysis of the oxetans from hexafluoroacetone yields (Z)- and (E)-1,2-difluoroethylene and the olefin (CF3)2C=CHF, the oxetan yields the olefins (Z)- and (E)-CHF=CHF and (CF2Cl)2C=CHF, and r-2-pentafluoroethyl- or heptafluoro-n-propyl-c-3,t-4-difluoro-oxetans yield mainly the olefins (Z)- and (E)-RFCHC=CHF (RF=C2F5 or n-C3F7).
