Hydrosilylation of Ketones, Imines and Nitriles Catalysed by Electrophilic Phosphonium Cations: Functional Group Selectivity and Mechanistic Considerations. Issue 17 (10th March 2015)

• Record Type: Journal Article
• Authors: Pérez, Manuel; Qu, Zheng‐Wang; Caputo, Christopher B.; Podgorny, Vitali; Hounjet, Lindsay J.; Hansen, Andreas; Dobrovetsky, Roman; Grimme, Stefan; Stephan, Douglas W.
• Is Part Of: Chemistry. Volume 21:Issue 17(2015)
• Page Start: 6491
• Page End: 6500
• Publication Date: 2015-03-10
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201406356
• Languages: English
• ISSNs: 0947-6539

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>The electrophilic phosphonium salt, [(C₆F₅)₃PF][B(C₆F₅)₄], catalyses the efficient hydrosilylation of ketones, imines and nitriles at room temperature. In the presence of this catalyst, adding one equivalent of hydrosilane to a nitrile yields a silylimine product, whereas adding a second equivalent produces the corresponding disilylamine. [(C₆F₅)₃PCl][B(C₆F₅)₄] and [(C₆F₅)₃PBr][B(C₆F₅)₄] are also synthesised and tested as catalysts. Competition experiments demonstrate that the reaction exhibits selectivity for the following functional groups in order of preference: ketone&gt;nitrile&gt;imine&gt;olefin. Computational studies reveal the reaction mechanism to involve initial activation of the SiH bond by its interaction with the phosphonium centre. The activated complex then acts cooperatively on the unsaturated substrate.</p> </abstract>