B(C6F5)3‐Catalyzed Transfer of Dihydrogen from One Unsaturated Hydrocarbon to Another. Issue 41 (26th August 2015)

• Record Type: Journal Article
• Authors: Chatterjee, Indranil; Qu, Zheng‐Wang; Grimme, Stefan; Oestreich, Martin
• Is Part Of: Angewandte Chemie international edition. Volume 54:Issue 41(2015)
• Page Start: 12158
• Page End: 12162
• Publication Date: 2015-08-26
• Subjects: Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201504941
• Languages: English
• ISSNs: 1433-7851

Abstract

<abstract abstract-type="main" xml:lang="en"> <title>Abstract</title> <p>A transition‐metal‐free transfer hydrogenation of 1, 1‐disubstituted alkenes with cyclohexa‐1, 4‐dienes as the formal source of dihydrogen is reported. The process is initiated by B(C₆F₅)₃‐mediated hydride abstraction from the dihydrogen surrogate, forming a Brønsted acidic Wheland complex and [HB(C₆F₅)₃]⁻. A sequence of proton and hydride transfers onto the alkene substrate then yields the alkane. Although several carbenium ion intermediates are involved, competing reaction channels, such as dihydrogen release and cationic dimerization of reactants, are largely suppressed by the use of a cyclohexa‐1, 4‐diene with methyl groups at the C1 and C5 as well as at the C3 position, the site of hydride abstraction. The alkene concentration is another crucial factor. The various reaction pathways were computationally analyzed, leading to a mechanistic picture that is in full agreement with the experimental observations.</p> </abstract>