Formation and characterization of neutral and cationic amino(thio)carbene complexes of gold(I) from thiazolyl precursors

Abstract

Benzothiazole-2-yl-, 4-methylthiazolyl- and thiazolyl-lithium reacted with [AuCl(tht)](tht = tetrahydrothiophene) to form bis(thiazolyl)aurate compounds which can be protonated or alkylated to give mono- and bis-(carbene) complexes of the type [Au([graphic omitted])([graphic omitted])] and [Au(CNRCX¹= CX²S)₂]⁺(X¹X²= C₄H₄; X¹= Me, X²= H; X¹= X²= H; R = H or Me). The strongly ligated gold phosphine and perfluorophenyl complexes [AuCl(PPh₃)] and [Au(C₆F₅)(tht)] as well as AuCN also reacted with the thiazolyllithiums to afford, upon protonation or alkylation, cationic and neutral carbene compounds. Complicating side-reactions, such as homoleptic rearrangement, protonation or alkylation on carbon rather than nitrogen and dissociative polymerization were observed. The crystal structure of the neutral mono(carbene) complex [Au([graphic omitted])([graphic omitted])] shows a gold–gold interaction with a distance of 3.075(1)Å.