Chemoselective oxidative addition of vinyl sulfones mediated by palladium complexes bearing picolyl-N-heterocyclic carbene ligands. Issue 17 (15th April 2020)

• Record Type: Journal Article
• Authors: Scattolin, Thomas; Santo, Claudio; Demitri, Nicola; Canovese, Luciano; Visentin, Fabiano
• Is Part Of: Dalton transactions. Volume 49:Issue 17(2020)
• Page Start: 5684
• Page End: 5694
• Publication Date: 2020-04-15
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d0dt01144d
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : We have examined in depth the features of oxidative addition of ( E )-1, 2 ditosylethene on palladium(0) complexes bearing picolyl-N-heterocyclic carbenes. Abstract : The manifold interactions of ( E )- or ( Z )-1, 2-ditosylethene with a palladium(0) centre bearing picolyl-NHC carbene ligands have been studied thoroughly. ( E )-1, 2-Ditosylethene produces the expected and stable η 2 -olefin palladium complexes, whereas the coordination of the Z derivative alternatively promotes the isomerization of the olefin itself or an oxidative addition process depending on the steric bulkiness of carbene substituents and/or the adopted synthetic procedure. Remarkably, the oxidative addition pathway involves a selective S -vinyl (not S -aryl) breaking and produces selectively the S- rather than O-coordinated sulfinate. A mechanistic study has clarified the reasons of the chemoselectivity of the process, which was proved to be kinetically controlled. All the involved species have been isolated and exhaustively characterized. In particular, we report the first example of the X-ray crystal structure of a complex bearing one vinyl and one S-sulfinate fragment coordinated to palladium.