Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, Hsinchu 30010, Taiwan.
J Chem Phys. 2013 Aug 28;139(8):084320. doi: 10.1063/1.4818880.
Irradiation at 193 nm of a p-H2 matrix containing acryloyl chloride CH2CHC(O)Cl at 3.2 K yielded infrared absorption lines at 3143.6 (ν1), 3057.0 (ν2), 3048.0 (ν3), 2103.1 (ν4), 1461.0 (ν5), 1349.8 (ν6), 1223.7 (ν11+ν12 or 2ν12), 1092.8 (ν8), 918.1 (ν9), 691.0 (ν10), 624.3 (ν11), and 597.1 (ν12) cm(-1) that are assigned to the 3-propenonyl (·CH2CHCO) radical. The assignments are based on the photolytic behavior and a comparison of observed vibrational wavenumbers and infrared intensities with those predicted with the B3PW91/aug-cc-pVDZ method. The observation is consistent with a major radical formation channel CH2CHCO + Cl followed by escape of the Cl atom from the original p-H2 cage. The observation of 3-propenonyl (·CH2CHCO) radical but not 3-propenalyl (s-cis- or s-trans-CH2CHĊO) radical indicates that the former is the most stable isomer and that the barrier heights for conversion from s-cis- or s-trans-CH2CHĊO to ·CH2CHCO are small.
在 3.2 K 下，用 193nm 光辐照含有丙烯酰氯 CH2CHC(O)Cl 的 p-H2 基质，得到红外吸收谱线，位于 3143.6（ν1）、3057.0（ν2）、3048.0（ν3）、2103.1（ν4）、1461.0（ν5）、1349.8（ν6）、1223.7（ν11+ν12 或 2ν12）、1092.8（ν8）、918.1（ν9）、691.0（ν10）、624.3（ν11）和 597.1（ν12）cm-1，这些谱线被分配给 3-丙烯酰基（·CH2CHCO）自由基。这些分配是基于光解行为以及观察到的振动波数和红外强度与用 B3PW91/aug-cc-pVDZ 方法预测的数值进行比较的结果。观察结果与主要的自由基形成通道 CH2CHCO + Cl 一致，随后 Cl 原子从原始 p-H2 笼中逸出。观察到 3-丙烯酰基（·CH2CHCO）自由基而不是 3-丙烯醛基（顺式或反式-s-CH2CHĊO）自由基表明，前者是最稳定的异构体，并且从顺式或反式-s-CH2CHĊO 转化为·CH2CHCO 的势垒高度较小。
