35576-88-6Relevant articles and documents
Kinetics of the Reactions of FC(O)O Radicals with NO, NO2, O3, O(3P), CH4, and C2H6
Moers, V.,Arguello, G. A.,Hoffmann, A.,Malms, W.,Roeth, E. P.,Zellner, R.
, p. 15899 - 15910 (1995)
Rate coefficients for the reactions of FC(O)O radicals with NO, NO2, O3, O(3P), CH4, and C2H6 were measured as a function of temperature and total pressure in the range 235-293 K and 9-210 mbar (N2).FC(O)O radicals were generated using the excimer laser photolysis of bis(fluoroformyl) peroxide (FC(O)OO(O)CF) at 193 nm.Time-resolved detection of FC(O)O was achieved by absorption measurements in the 305-band around 617.5 nm using a tunable narrow band ring dye laser as a light source.At this wavelength the absolute decadic absorption cross section was found to be ?(FC(O)O)617.5=(7.1+/-2.6)*10-18 cm2.The following rate coefficients were determined: k8(FC(O)O+NO->CO2+FNO)=(3.8+/-0.5)*10-11 cm3/s, independent of temperature and pressure, k9,infinite(FC(O)O+NO2->products)=(5.3+/-1.2)*10-12(T/300)-(2.5+/-1) cm3/s, k11(FC(O)O+O3->products) 2.5*10-14 cm3/s at 293 K, k14(FC(O)O+O(3P)->products)=(8.8+/-2.0)*10-12 cm3/s at 293 K, k18(FC(O)O+CH4->products 4*10-18 cm3/s at 293 K, and k19(FC(O)O+C2H6->FC(O)OH+C2H5)=(1.15+/-0.75)*10-13 exp cm3/s.It is concluded that the reactivity of FC(O)O toward these reagents resembles that of the NO3 radical.The reactions involving NOx represent the dominant reactive removal pathways of FC(O)O under all atmospheric conditions.However, even these reactions are not competitive with the photochemical degradation of FC(O)O in the sunlit atmosphere.The effect of FC(O)O chemistry on the stratospheric ozone layer is negligible.
Surface Chemistry of Perfluoroether: A Study of the Reaction Mechanism of (C2F5)2O with an Al2O3 Surface by FTIR Spectroscopy
Lyth, E.,Ng, L. M.
, p. 17615 - 17623 (2007/10/03)
The decomposition of perfluorodiethyl ether on alumina has been studied at 300 and 500 K by transmission infrared spectroscopy using excess ether under high-pressure conditions.It was found in this study that the reaction products include trifluoro-, difluoro-, and monofluoroacetate, fluoroformate, alkyl acetate, and alkyl formate.The initial formation of trifluoroacetate probably results from a nucleophilic attack at the α-carbon of the ether by a surface oxygen anion.Subsequently, fluorine atoms, abstracted by coordinately unsaturated (cus) aluminum atoms, are replaced by hydrogen atoms donated by isolated surface hydroxyls.There is also evidence that fluoroalkene and fluoroalkyne resulted from the decomposition of initial surface adsorbates.
Process for the preparation of fluoroformates
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, (2008/06/13)
A process for the preparation of fluoroformates of formula: STR1 in which R1 is a substituted or unsubstituted, saturated or unsaturated aliphatic, cycloaliphatic or polycyclic radical, or substituted or unsubstituted araliphatic radical or an aromatic radical, which consists of reacting a carbonate of formula: STR2 in which R1 has the same meaning as hereinabove and R2 is hydrogen, alkyl of 1-12 carbon atoms, cycloalkyl of 5-12 carbon atoms, saturated or unsaturated, unsubstituted or substituted by one or more halogen atoms or R2 is aryl, unsubstituted or substituted by one or more halogen atoms, with an alkali or alkaline earth fluoride, ammonium fluoride or a quaternary ammonium fluoride, of formula FNR3 R4 R5 R6, wherein R3, R4, R5, R6 are the same or different and are hydrogen, alkyl or aralkyl of 1-12 carbon atoms or a fluoride which is KHF2, NH4 HF2 or KSO2 F. The fluoride is activated by a complexing agent for the cation which is a cryptate, a cyclic or linear polyether or by means of a polar aprotic compound. The carbonate is split to give a reaction mixture containing an aldehyde and the fluoroformate which is removed from the reaction mixture.
