Matrix Isolation and Theoretical Study on the Photolysis of CH2ClCOCl
Nobuaki Tanaka *
Department of Environmental Science and Technology, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan
Mayuko Nakata
Department of Environmental Science and Technology, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan
*Author to whom correspondence should be addressed.
Abstract
UV light photolysis of chloroacetyl chloride (CH2ClCOCl) has been investigated using infrared spectroscopy in cryogenic Ar, Kr, Xe and O2 matrices. In all matrices, CHCl=C=O, HCl, CH2Cl2 and CO were produced, with the relative yields depending on the used matrix gas. The relative yield of CH2Cl2 formation to CHCl=C=O formation was greatly enhanced in Xe because of the external heavy atom effect, indicative of the formation of CH2Cl2 via the C–C or C–Cl bond cleavage in the triplet state. In CH2ClCOCl/Ar, photoisomerization from anti- to gauche-CH2ClCOCl was also observed at the early stage of the irradiation. The results show that in Ar, the reactions predominantly proceed through concerted mechanisms.
Keywords: Chloroacetyl chloride, photolysis, cryogenic matrix, Ketene