A Ligand-Free Pt₃ Cluster Catalyzes the Markovnikov Hydrosilylation of Alkynes with up to 10p>6p> Turnover Frequencies

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• 作者：Miguel A. Rivero-Crespo ; Dr. Antonio Leyva-P&eacute ; rez and Prof. Avelino Corma
• 刊名：Chemistry - A European Journal
• 出版年：2017
• 出版时间：January 31, 2017
• 年：2017
• 卷：23
• 期：7
• 页码：1702-1708
• 全文大小：1597K
• ISSN：1521-3765

文摘

The Pt-catalyzed hydrosilylation of alkynes is the procedure of choice to obtain vinylsilanes, and is claimed to be the most relevant application of Pt in organic synthesis. More than half a century after its discovery, only β-vinylsilanes (anti-Markovnikov addition) are obtained with simple Pt catalysts, whereas α-vinylsilanes (Markovnikov addition) remain elusive compounds. Here the catalysis of the Markovnikov hydrosilylation of terminal alkynes by Pt₃ clusters, in parts-per-million amounts, to give a wide variety of α-vinylsilanes in reasonable isolated yields and with turnover frequencies that can reach up to one million per hour is reported. Moreover, these α-vinylsilanes are reactive in well-stablished C−C bond-forming cascade reactions, in which the corresponding β-isomers are unreactive. Besides its efficiency and synthetic usefulness, this catalytic system is an excellent example of how the atom-by-atom aggregation of a catalytic metal leads to a different selectivity for a given reaction