Liu Chenghuan, Liu Rui, Wang Chenfeng, Tang Yanyan, Zhang Zheng-Feng, Su Ming-Der, Li Yan
College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou 311121, China.
Key Laboratory of Silicone Materials Technology of Zhejiang Province, Hangzhou Normal University, Hangzhou 311121, China.
Inorg Chem. 2022 Oct 10;61(40):15864-15870. doi: 10.1021/acs.inorgchem.2c01762. Epub 2022 Sep 30.
The reactions of amidinate silylene chloride LSi(:)Cl (L = PhC(NBu)) with TMS- and Ph-ethynyl lithium salts gave rise to silacycles and , respectively. The formation of and may undergo cyclo-condensations of transient ethynylsilylene intermidiates and the activation of an amidinate backbone. The distinct structures of and may be derived from the different electronic or steric properties of ethynyl substituents, and their formation mechanisms were investigated by density functional theory (DFT) calculations. Moreover, a sequential reaction of LSi(:)Cl with BH·SMe and TMSC≡CLi as well as a reaction of LSi(:)Cl with TMSC≡CLi under O exclusively obtained ethynylsilanes and , respectively, which indicated that either blocking a lone pair of a Si(II) atom or oxidizing Si(II) to Si(IV) prevents the further conversion of ethynylsilylenes to silacycle . All products were characterized by NMR spectroscopy and X-ray crystallography.
脒基亚甲硅烷基氯LSi(:)Cl（L = PhC(NBu)）与TMS-乙炔基锂盐和Ph-乙炔基锂盐的反应分别生成了硅杂环 和 。 和 的形成可能经历了瞬态乙炔基亚甲硅烷基中间体的环缩合以及脒基主链的活化。 和 独特的结构可能源自乙炔基取代基不同的电子或空间性质，并且通过密度泛函理论（DFT）计算研究了它们的形成机理。此外，LSi(:)Cl与BH·SMe和TMSC≡CLi的顺序反应以及LSi(:)Cl与TMSC≡CLi在O存在下的反应分别仅得到乙炔基硅烷 和 ，这表明要么阻断Si(II)原子的孤对电子，要么将Si(II)氧化为Si(IV)，都能阻止乙炔基亚甲硅烷基进一步转化为硅杂环 。所有产物均通过核磁共振光谱和X射线晶体学进行了表征。
