Nature China highlighted Li-Juan’s JACS
吴云东课题组和港科大孙建伟课题组发表的研究论文被Nature China亮点推荐
2013年10月2日，Nature China 亮点推荐了吴云东课题组和香港科技大学孙建伟课题组近期发表在《Journal of the American Chemical Society》（影响因子10.68），题为“Ligand-Controlled Remarkable Regio- and Stereodivergence in Intermolecular Hydrosilylation of Internal Alkynes: Experimental and Theoretical Studies”的研究论文。
乙烯基硅烷在不仅在高分子领域中应用广泛，也是有有机合成中重要的中间体，经过转化可以得到一系列不同的化合物。通过硅氢化反应是制备乙烯基硅烷的一个主要方法。传统的二取代炔烃硅氢化反应通常很难控制反应的区域选择性和立体选择性而得到混合产物。近期，香港科技大学的孙建伟教授课题组发现Ru（Ⅱ）金属配合物催化的炔烃硅氢化反应具有高度的区域选择性和立体选择性，首次实现了用配体Cp和Cp*同时控制二取代炔烃硅氢化反应的区域选择性和立体选择性。
为了研究该反应的高度选择性是如何实现的。我院吴云东教授课题组对这个反应的机理进行了研究。经过理论计算发现几种传统的机理对这个反应都不适用。该反应的机理是经过氧化加成的转金属化，异构化和还原硅迁移，不同的配体Cp和Cp*和底物的空间位阻不同从而导致选择性不同。空间位阻在选择性中起主导作用，炔烃取代基(如硅烷基团)和配体的协同作用最终决定了反应的区域和立体选择性。理论计算结果和实验观测结果符合。理论上预测出具有较大空间位阻的其他底物也能得到相同的选择性，进一步实验表明该预测与实验相符。
论文链接：
http://pubs.acs.org/doi/abs/10.1021/ja405752w
Nature China亮点推荐链接：http://www.nature.com/nchina/2013/131002/full/nchina.2013.93.html
Professor Wu Yun-Dong and Jianwei Sun at HKUST’s research paper has been highlighted on Nature China
On Oct. 2nd, 2013, the paper from Professor Wu Yun-Dong and Jianwei Sun at HKUST’s group has been highlighted on Nature China. The paper published in JACS is entitled “Ligand-Controlled Remarkable Regio- and Stereodivergence in Intermolecular Hydrosilylation of Internal Alkynes: Experimental and Theoretical Studies”.
Vinylsilanes are not only widely used in polymer, but also important building blocks in organic synthesis. A wide range of useful organic compounds can be obtained by various transformations of vinylsilanes. Hydrosilation of alkynes is one of the important methods for preparing vinylsilanes. The traditional methods for hydrosilylation of internal alkynes are difficult to control the selectivity, showing poor regioselectivity and stereoselectivity with mixture products. Recently, Professor Sun Jianwei in HKUST found that Ru (Ⅱ) metal complexes catalyzed alkyne hydrosilylation present high regioselectivity and stereoselectivity. It is the first time to control the regioselectivity and stereoselectivity of internal alkynes by ligands Cp and Cp *.
To study how this highly selective achieved, Professor Wu Yun-Dong’s research group carried out mechanistic study. Theoretical studies indicated that several traditional mechanisms are not applicable to this reaction. The mechanism of the reaction undergoes by: oxidative-added trasmetalation, isomerization and reductive sily migration. Different ligands Cp and Cp * showed different steric repulsions with substrates, thus result different selectivity. Steric effect plays a critical role in governing the regio- and stereoselectivity, and the synergistic interplay between the substituent in the alkyne (e.g., silyl group) and the ligand that ultimately determines the observed remarkable regio- and stereodivergence. Computational results are consistent with the experimental observations. It is predicted theoretically that the same selectivity can be obtained by using other substrates having a large steric hindrance group (e.g. tertbutyl group). Further experiments showed that the prediction is in accordance with experiment.
Link of the paper:
http://pubs.acs.org/doi/abs/10.1021/ja405752w
Link of the Nature China highlight:
http://www.nature.com/nchina/2013/131002/full/nchina.2013.93.html