The reaction of photochemically generated CF3O radicals with CO

Abstract

CF 3 O 2 CF 3 was photolyzed at 254 nm in the presence of CO in 760 torr N 2 or air at 296 K in a static reactor. In N 2 , the products CF 3 OC(O)C(O)OCF 3 and CF 3 OC(O)O 2 C(O)OCF 3 were detected by FTIR spectroscopy. In air, the only observed products were CF 2 O and CO 2 and a chain process, initiated by CF 3 O, was invoked for the conversion of CO to CO 2 . From both product studies, a mechanism for the CF 3 O initiated oxidation of CO was derived, involving the addition reaction CF 3 O 2 ϩ CO CF 3 OC(O). The rate constant for the reaction CF 3 O ϩ CO at 296 K at a total pressure of 760 torr air was determined to be k(

Bis(trifluoromethyl)dicarbonate, CF3OC(O)OC(O)OCF3

“…The CF 3 O radical is an effective catalyst in the oxidation of atmospheric carbon monoxide [3][4][5]. In laboratory studies on the mechanism of the reaction of CF 3 O x (x = 1, 2) radicals with O 2 and CO (at much higher concentrations than those found in the natural atmosphere) new CF 3 O derivatives have been detected well before the atmospheric chemistry of these compounds came to light.…”

“…In laboratory studies on the mechanism of the reaction of CF 3 O x (x = 1, 2) radicals with O 2 and CO (at much higher concentrations than those found in the natural atmosphere) new CF 3 O derivatives have been detected well before the atmospheric chemistry of these compounds came to light. In the late sixties the fast reaction between CF 3 O radicals and CO led to the synthesis of the oxalic acid derivative CF 3 OC(O)-C(O)OCF 3 [6].…”

The Trifluoromethoxycarbonyl Radical CF3OCO

“…[9] Catalytic oxidation of CO to CO 2 using CF 3 O radicals (generated photochemically from the peroxide CF 3 OOCF 3 ) has been previously observed. [10] The mechanism also included the existence of the radicals CF 3 OCO and CF 3 OC(O)OO. Starting from CF 3 O radicals, the proposed reaction pathway [7,10,11] is as follows [Eqs.…”

“…[10] The mechanism also included the existence of the radicals CF 3 OCO and CF 3 OC(O)OO. Starting from CF 3 O radicals, the proposed reaction pathway [7,10,11] is as follows [Eqs. (4) see above, (6) to (8)].…”

“…[12] These preparative studies strongly support the proposed reaction mechanism of the early kinetic studies. [10,11] Both stable carbonate derivatives CF 3 OC(O)OOCF 3 and CF 3 OC(O)OOC(O)OCF 3 are reservoir species for CF 3 O radicals. [7] Moreover, they are used for generating CF 3 O radicals by vacuum flash pyrolysis according to Equations (14) and (15) and subsequent isolation of the products in noble gas matrices, CF (15) and for recording the complete IR and UV spectra of CF 3 O for the first time.…”