Faculty of Chemistry, University of Wrocław, Wrocław, Poland.
J Phys Chem A. 2013 Aug 29;117(34):8263-73. doi: 10.1021/jp4047837. Epub 2013 Aug 16.
We report the results of the theoretical study of (•)OH-induced oxidative cleavage of dimethyl disulfide (DMDS) and the experimental study of the CH3SSCH3 + (•)OH reaction in the presence of (•)NO. Infrared low temperature argon matrix studies combined with ab initio calculations allowed us to identify cis-CH3SONO, which evidences the formation of the CH3SO(•) and CH3SH molecules in the course of the CH3SSCH3 + (•)OH reaction. Ab initio/quantum chemical topology calculations revealed details of the oxidative cleavage of dimethyl disulfide, which is a complex multistep process involving an alteration of S-O and S-S covalent bonds as well as a hydrogen atom transfer. The ability of delocalization of the unpaired electron density by sulfur atoms and a formation of a hydrogen bond by CH3SO(•) and CH3SH are the factors which seem to explain antiradical properties of DMDS.
我们报告了（•）OH 诱导的二甲基二硫（DMDS）氧化裂解的理论研究结果，以及在（•）NO 存在下 CH3SSCH3 +（•）OH 反应的实验研究结果。红外低温氩基质研究与从头算计算相结合，使我们能够识别 cis-CH3SONO，这证明了在 CH3SSCH3 +（•）OH 反应过程中形成了 CH3SO(•)和 CH3SH 分子。从头算/量子化学拓扑计算揭示了二甲基二硫氧化裂解的细节，这是一个复杂的多步过程，涉及 S-O 和 S-S 共价键的改变以及氢原子转移。硫原子对未配对电子密度离域的能力和 CH3SO(•)和 CH3SH 形成氢键的能力似乎解释了 DMDS 的抗氧化特性。
