Cyclic Amino(Ylide) Silylene: A Stable Heterocyclic Silylene with Strongly Electron‐Donating Character. Issue 52 (25th November 2016)

• Record Type: Journal Article
• Authors: Alvarado‐Beltran, Isabel; Baceiredo, Antoine; Saffon‐Merceron, Nathalie; Branchadell, Vicenç; Kato, Tsuyoshi
• Is Part Of: Angewandte Chemie international edition. Volume 55:Issue 52(2016)
• Page Start: 16141
• Page End: 16144
• Publication Date: 2016-11-25
• Subjects: heterocycles -- ligand design -- ligand effects -- main-group chemistry -- silylenes; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201609899
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: An isolable heterocyclic silylene (4 ) with two different π‐donating substituents, namely a classical amino group and a more electropositive and stronger carbon‐based π‐donating phosphonium ylide, was synthesized and fully characterized. The combination of these two different π‐donating substituents confers high thermal stability and an unusual nucleophilic character on silylene4 . Therefore, silylene4 behaves as a strong donor ligand toward transition metals with a donating character comparable to N ‐heterocyclic carbenes, in contrast to classical N ‐heterocyclic silylenes, which generally present a weak donating character. Abstract : An isolable cyclic silylene stabilized by two different strongly π‐donating groups, an amino group and a phosphonium ylide, was synthesized. The combination of these two π‐donating substituents confers high thermal stability and strong nucleophilic character on the silylene. Its electron‐donating character is comparable to that of NHC ligands, despite the fact that stable silylenes have been thought to be more weakly donating than phosphines.