CH₃CH₂–MH and (CH₂)₂–MH₂ were identified in the matrix IR spectra from reactions of laser-ablated group 3 metal atoms with ethane, and they were characterized via theoretical investigations. The observed products are the most stable in the proposed reaction path. Because of the small number of valence electrons, the group 3 metal high oxidation-state complexes are less stable. The C–C insertion product [(CH₃)₂M], which was predicted to be more stable than the observed ones, was not observed probably because of the high energy barrier and a likely slower rate for insertion into one C–C bond than one of six C–H bonds. The C–C bond of the metallacyclopropanes is the shortest among the early transition-metal analogues, and its stretching frequencies are the highest, revealing the weakest interaction between the metal dihydride and ethylidene groups. The undetected ethylidene is not agostic, parallel to the previously examined methylidene.

中文翻译：

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激光烧蚀的3族金属原子与乙烷反应制备的插入和金属环丙烷配合物[CH ₃ CH ₂ -MH和（CH ₂）₂ -MH ₂ ]的基质红外光谱

通过激光烧蚀的3族金属原子与乙烷的反应，在基质红外光谱中鉴定出CH ₃ CH ₂ -MH和（CH ₂）₂ -MH ₂，并通过理论研究对其进行了表征。观察到的产物在建议的反应路径中最稳定。由于价电子数量少，第3族金属的高氧化态络合物不稳定。C–C插入产物[（CH ₃）₂M]，据预测比观察到的更稳定，但未观察到这可能是由于较高的能量势垒以及插入一个C-C键的速度可能比六个C-H键之一慢的缘故。在早期过渡金属类似物中，金属环丙烷的C–C键最短，并且其拉伸频率最高，表明二氢金属与亚乙基之间的相互作用最弱。未检测到的亚乙炔基是有害的，与先前检查过的亚甲叉基平行。