Pyrazolates, gold

Au-C bonds, mixed metal gold-silver dimers of planar, trinuclear complexes are readily formed by mixing gold(I) carbeniates and gold(I) benzylimidazolates with silver(I) pyrazolates in stoichiometric ratios. The complexes retain the ligands associated with the metal atoms of the starting materials. 

Yang, G. and Raptis, R.G. (2003) Synthesis, structure and properties of tetrameric gold(I) 3,5-di-tert-butyl—pyrazolate. Inorganica Chimica Acta, 352, 98—104. 

Bonati, F., Burini, A., Pietroni, B.R. and Galassi, R. (1993) Gold(I) Derivatives of Furan, Thiophene, 2-mercaptopyridine, and of some Pyrazoles — Mass-spectroscopic evidence of tetranuclear Gold(l) compounds. CazzMa Chimica Itcdiana, 123, 691. 

Barranco, E.M., Gimeno, M.C., Laguna, A. and Villacampa, M.D. (2005) Gold and silver complexes with the ferrocenyl-pyrazolate ligand FcCH2pz. Inorganica Chimica Acta, 358 (14), 4177 182. 

Figure 8.27 Stacking of two gold pyrazolate trimers into a discotic dimer of trimers.

Kim, S.J., Kang, S.H., Park, K.-M., Kim, H Zin, W.-C., Choi, M.-G. and Kim, K. (1998) Trinuclear Gold(l) Pyrazolate Complexes Exhibiting Hexagonal Columnar Mesophases with Only Three Side Chains. Chemistry of Materials, 10, 1889-1893. 

Ovejero, P., Mayoral, M.J., Cano, M. and Lagunas, M.C. (2007) Luminescence of neutral and ionic gold(l) complexes containing pyrazole or pyrazolate-type ligands. Journal of Organometallic Chemistry, 692, 1690-1697. 

With the previously demonstrated ability of trinuclear gold(I) pyrazo-late complexes that possess long-alkyl chains to form columnar mesophases [119-121], Aida and co-workers synthesized a series of luminescent Au3 complexes bearing dendritic poly(benzyl ether) functionalized pyrazole ligands [122]. By controlling the dendron generation, superhelical fibres with extensive inter molecular Au3 stacking could be obtained, which resulted in an... 

Group V. N-Donor ligands. Reaction of [AuCl(Me2S)] with 1-unsubstituted pyrazoles in methanolic KOH has yielded N-pyrazolyl gold(i) derivatives.225 The white compounds are stable to air, light, and heat, and molecular weight measurements show they are trimeric in both vapour and CHC13 solution, and on this basis, and i.r. evidence, structure (59) was proposed. 

Most pyrazole complexes are inert to moist air, with only the silver and gold compounds 206 and 207 showing limited stability 178). The X-ray structures of the unsubstituted thorium and uranium derivatives 209a and 210a, which are isostructural, have been reported 280). The hexafluoro-acetonylpyrazole complexes are listed in Table IX. 

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