Synthesis and structural characterisation of linear Au(I) N-heterocyclic carbene complexes: New analogues of the Au(I) phosphine drug Auranofin

• Published in: Journal of organometallic chemistry Vol. 690; no. 24; pp. 5625 - 5635
• Main Authors: Baker, Murray V., Barnard, Peter J., Berners-Price, Susan J., Brayshaw, Simon K., Hickey, James L., Skelton, Brian W., White, Allan H.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2005
• Subjects: Auranofin; Gold complexes; N-heterocyclic carbene complexes; N-heterocyclic carbene complexes; Gold complexes; Auranofin
• ISSN: 0022-328X; 1872-8561
• DOI: 10.1016/j.jorganchem.2005.07.013

The synthesis and structural characterisation of a series of neutral Au(I) N-heterocyclic carbene complexes [(NHC)AuX] (X = Cl and 2′,3′,4′,6′-tetra- O-acetyl-β- d-glucopyranosyl-1-thiolato) are reported. These compounds are of interest as potential new antitumour drugs. The synthesis and characterisation of a series of neutral Au(I) N-heterocyclic carbene complexes [(NHC)AuX] (X = Cl and 2′,3′,4′,6′-tetra- O-acetyl-β- d-glucopyranosyl-1-thiolato) are reported. The chloro complexes were synthesised either by reaction of the appropriate 1,3-dialkylimidazol-2-ylidene with [(Me 2S)AuCl] or by transmetallation between the appropriate Ag(I)–NHC complex and [(Me 2S)AuCl]. The 2′,3′,4′,6′-tetra- O-acetyl-β- d-glucopyranosyl-1-thiolato complexes were prepared from the appropriate [(NHC)Au(I)Cl] complex and 2′,3′,4′,6′-tetra- O-acetyl-1-thio-β- d-glucopyranose under basic conditions. A cationic Au(I)–NHC triphenylphosphine adduct was also prepared. Structural studies (X-ray diffraction) of a number of the complexes show that in each case the gold atom is (quasi-) linearly two-coordinate, having C–Au–Cl, C–Au–S or C–Au–P coordination. In one case, a new phase of [(Cy 2Im)AuCl], the molecules pack pair-wise with a close Au⋯Au interaction (3.1566(6) Å). Preliminary studies show this complex is luminescent in the solid state.