Products and reaction paths in the liquid phase oxidation of trans-1,2-dichloroethene with oxygen

Abstract

Ultraviolet initiated liquid phase oxidation of neat trans-1,2-dichloroethene (1a) with oxygen at 30 °C afforded ca. 45% of the combined Cl-products CO, CO2, and phosgene as well as nine oxygenated and nine non-oxygenated chlorinated organic products. Major oxygenated products were cis- and trans-2,3-dichlorooxirane (6a, b) and 1,2,2-trichloroethyl formate (13); minor products were e.g., meso and rac bis(1,2,2-trichloroethyl) ether (11c, d) and dichloromethyl 1,2,2-trichloroethyl ether (12). The mode of formation of all products is rationalized by a unified reaction scheme.

Photodestruction of CCl4 on MgO Films with/without Water

“…6a OCCl 2 was produced from UV-irradiated liquid phase oxidation of CH 2 ClCH 2 Cl. 15 Gas phase photodestruction over TiO 2 powders of various chlorinated ethylenes was found to sometimes produce phosgene and Cl 2 and other species in addition to HCl, H 2 O, and CO 2 . 16 Golovanova et al 12 studied the photocatalytic decomposition of CCl 4 on a silicon surface in the presence of chemisorbed water and reported OCCl 2 formation.…”

“…CCl 4 passed over a Fe 2 O 3 produced CO 2 , Cl 2 , C 2 Cl 4 , and also a small amount of OCCl 2 . The latter was believed to be a “short-lived intermediate.” 6a OCCl 2 was produced from UV-irradiated liquid phase oxidation of CH 2 ClCH 2 Cl . Gas phase photodestruction over TiO 2 powders of various chlorinated ethylenes was found to sometimes produce phosgene and Cl 2 and other species in addition to HCl, H 2 O, and CO 2 …”

Photochemically Induced Reactions of Ozone with 1,2-Dibromoethene and 1,2-Dichloroethene: An FT-IR Matrix Isolation Study

“…The carbonyl and carbon monoxide species detected in the ozone experiments were also detected in experiments involving a solid oxygen matrix or nitrogen dioxide; this, and the fact that XHCdCdO were detected, implies that a different pathway from that of ozonolysis is being followed, one which involves the reaction of O atoms with the halogenated ethene to form similar carbonyl and carbon monoxide species. However, there are many feasible routes by which the reaction could proceed 20,21,[52][53][54] also occur from reaction pathways (i) and (ii), respectively (Scheme 2). The excited species CHXCHXO* represents several possible excited-state structures, including that of the epoxide (iii) which has been tentatively identified in these experiments and elsewhere.…”

“…Matrix isolation studies of the ozone/alkene reaction have made possible the full characterization of the POZ and SOZ intermediates by infrared spectroscopy. ,,, However to initiate the reaction, most of the matrices had to be warmed to relatively high temperatures (77 K for a N 2 matrix, 80−100 K for a Xe matrix, 25 K for an amorphous CO 2 matrix, 77 K for a crystalline CO 2 matrix, and 44 K for an Ar matrix 9 ) before any new bands appeared. Besides ozonolysis, the oxidation of halogenated alkenes with O( 3 P) atoms , or O 2 , has been shown to afford a range of oxygenated organic products and to eliminate small molecules such as CO, CO 2 , and X 2 . Furthermore, in some studies the elimination of HCl has been noted from chlorinated alkenes upon photolysis to yield an alkyne species.…”

Large-diameter self-assembled dimers of α,γ-cyclic peptides, with the nanotubular solid-state structure of cyclo-[(l-Leu-d-MeN-γ-Acp)4-]·4CHCl2COOH

“…Conclusive proof of the dimerization of 3b was provided by X-ray crystallography of the colourless prismatic crystals of 3b?4CHCl 2 COOH{ that were obtained from a solution of this CP in tetrachloroethane (the dichloroacetic acid presumably 9 having been formed by light-induced oxidation of the solvent). The asymmetric unit of these crystals comprises four discrete moieties: two L-Leu-D-Me N-c-Acp units, and two CHCl 2 COOH molecules.…”