Matrix isolation and theoretical study on the photolysis of trichloroacetyl chloride

Abstract

UV photolysis of CCl 3 COCl has been investigated by infrared spectroscopy in cryogenic Ar and O 2 matrices. In the Ar matrix, CCl 4 and CO were found to be dominant products over Cl 2 C=C=O. The CCl 3 and COCl species, observed as intermediates, indicated C-C bond cleavage. The C-C bond cleavage was also evidenced by the formation of ClC(O)OO in the O 2 matrix. The marked difference in the photochemistry of matrix-isolated CCl 3 COCl from that of CH 3 COCl, where CH 2 =C=O is the predominant product, can be attributed to the triplet surface reaction of CCl 3 COCl, as supported by the present DFT calculations.

Matrix isolation studies of 185nm light-induced cage reactions of o-chlorobenzaldehyde

“…As a result of the photolysis of O 2 upon 185.0 nm excitation, ozone was produced at 1037 cm −1 [16]. A strong band at 2342 cm −1 was assigned to CO 2  3 [17]. Unfortunately, we could not determine the reason for the absence of the peaks due to benzoyl chloride.…”

A theoretical study on decomposition and rearrangement reaction mechanism of trichloroacetyl chloride (CCl3COCl)

“…In some processes the transition structures were found to be close to the products because of the very short life time of those TSs. Phospogene (COCl 2 ), dichloroketene (CCl 2 CO), Carbon dichloride (CCl 2 ), Carbon tetrachloride (CCl 4 ), and Carbon monoxide (CO) are the major dominant products on the decomposition of the trichloroacetyl chloride and these products are experimentally observable [15]. These products are found to be highly hazards than the parent trichloroacetyl chloride molecules.…”

“…Furthermore, in the atmosphere at suitable condition this resultant product of trichloroacetyl chloride have probability of dissociation and rearrange to form most hazardous pollutants, such as phosgene, carbon monoxide, carbon tetrachloride, and so forth. Takumi Tamezane et al [15] previously reported that the trichloroacetyl chloride undergoes various possible reaction channels to release the major pollutants, such as carbon monoxide, carbon tetrachloride, and a minor quantity of phosgene to the atmosphere on UV irradiation. But, the detailed information to the product channels, product distributions, and reaction kinetics are still missing.…”

Photoinduced rotamerization and dissociation of o -fluorobenzoyl chloride in solid Ar

“…The latter band behaved as a group A band after prolonged irradiation. Ketene species and CO absorption bands are known to emerge in the ~2140 cm -1 region [14][15][16]. In fact, in the photolysis of benzoyl chloride the ketene product showed the absorption band assigned to the C=C=O asymmetric stretching vibration at 2120 cm -1 and the CO product showed the absorption band at 2138 cm -1 [6].…”