A Mechanistically and Operationally Simple Route to Metal–N‐Heterocyclic Carbene (NHC) Complexes. Issue 20 (12th March 2020)

• Record Type: Journal Article
• Authors: Tzouras, Nikolaos V.; Nahra, Fady; Falivene, Laura; Cavallo, Luigi; Saab, Marina; Van Hecke, Kristof; Collado, Alba; Collett, Christopher J.; Smith, Andrew D.; Cazin, Catherine S. J.; Nolan, Steven P.
• Is Part Of: Chemistry. Volume 26:Issue 20(2020)
• Page Start: 4515
• Page End: 4519
• Publication Date: 2020-03-12
• Subjects: complexes -- mechanism -- N-heterocyclic carbenes -- synthesis -- weak bases; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.202000564
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: We have been puzzled by the involvement of weak organic and inorganic bases in the synthesis of metal–N‐heterocyclic carbene (NHC) complexes. Such bases are insufficiently strong to permit the presumed required deprotonation of the azolium salt (the carbene precursor) prior to metal binding. Experimental and computational studies provide support for a base‐assisted concerted process that does not require free NHC formation. The synthetic protocol was found applicable to a number of transition‐metal‐ and main‐group‐centered NHC compounds and could become the synthetic route of choice to form M–NHC bonds. Abstract : No free carbene required : Computational and experimental investigations of a weak base‐assisted synthetic route leading to metal–NHC complexes suggest a concerted mechanism is at play. The method is exemplified with metal and nonmetal centers and establishes its synthetic utility.