Yang Zhenghai, He Chao, Doddipatla Srinivas, Krasnoukhov Vladislav S, Azyazov Valeriy N, Mebel Alexander M, Kaiser Ralf I
Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI, 96822, USA.
Samara National Research University, Samara, 443086, Russian Federation.
Chemphyschem. 2020 Sep 2;21(17):1898-1904. doi: 10.1002/cphc.202000392. Epub 2020 Aug 11.
The methylgermylene species (HGeCH ; X A') has been synthesized via the bimolecular gas phase reaction of ground state methylidyne radicals (CH) with germane (GeH ) under single collision conditions in crossed molecular beams experiments. Augmented by electronic structure calculations, this elementary reaction was found to proceed through barrierless insertion of the methylidyne radical in one of the four germanium-hydrogen bonds on the doublet potential energy surface yielding the germylmethyl (CH GeH ; X A') collision complex. This insertion is followed by a hydrogen shift from germanium to carbon and unimolecular decomposition of the methylgermyl (GeH CH ; X A') intermediate by atomic hydrogen elimination leading to singlet methylgermylene (HGeCH ; X A'). Our investigation provides a glimpse at the largely unknown reaction dynamics and isomerization processes of the carbon-germanium system, which are quite distinct from those of the isovalent carbon system thus providing insights into the intriguing chemical bonding of organo germanium species on the most fundamental, microscopic level.
在交叉分子束实验的单碰撞条件下,通过基态次甲基自由基(CH)与锗烷(GeH)的双分子气相反应合成了亚甲基锗物种(HGeCH;X A')。通过电子结构计算进一步研究发现,该基元反应在二重态势能面上通过次甲基自由基在锗烷四个锗氢键之一中的无势垒插入进行,生成甲锗基甲基(CH GeH;X A')碰撞复合物。随后,氢从锗转移至碳,甲锗基(GeH CH;X A')中间体通过消除原子氢进行单分子分解,生成单线态亚甲基锗(HGeCH;X A')。我们的研究揭示了碳 - 锗体系中很大程度上未知的反应动力学和异构化过程,这些过程与等价位的碳体系截然不同,从而在最基本的微观层面上为有机锗物种引人入胜的化学键合提供了见解。