B(C6F5)3‐Catalyzed Selective Chlorination of Hydrosilanes. Issue 17 (21st March 2017)

• Record Type: Journal Article
• Authors: Chulsky, Karina; Dobrovetsky, Roman
• Is Part Of: Angewandte Chemie international edition. Volume 56:Issue 17(2017)
• Page Start: 4744
• Page End: 4748
• Publication Date: 2017-03-21
• Subjects: borane catalysis -- chlorination -- frustrated Lewis pairs -- Lewis acids -- silanes; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201700324
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: The chlorination of Si−H bonds often requires stoichiometric amounts of metal salts in conjunction with hazardous reagents, such as tin chlorides, Cl2, and CCl4 . The catalytic chlorination of silanes often involves the use of expensive transition‐metal catalysts. By a new simple, selective, and highly efficient catalytic metal‐free method for the chlorination of Si−H bonds, mono‐, di‐, and trihydrosilanes were selectively chlorinated in the presence of a catalytic amount of B(C6 F5 )3 or Et2 O⋅B(C6 F5 )3 and HCl with the release of H2 as a by‐product. The hydrides in di‐ and trihydrosilanes could be selectively chlorinated by HCl in a stepwise manner when Et2 O⋅B(C6 F5 )3 was used as the catalyst. A mechanism is proposed for these catalytic chlorination reactions on the basis of competition experiments and density functional theory (DFT) calculations. Abstract : Cl‐early a winning combination : Hydrosilanes underwent selective chlorination upon treatment with HCl in the presence of a catalytic amount of B(C6 F5 )3 with the liberation of H2 (see scheme). For the chlorination of di‐ and trihydrosilanes, the adduct Et2 O⋅B(C6 F5 )3 was found to be a more selective catalyst.