Use of phosphine gold acetylides [(R3P)AuC CR] to form phosphine gold derivatives of tetra-iron and penta-iron clusters

Five new gold acetylides, [AuC equivalent to CR], with hydroxyl or amino functions in the organic radical R have been prepared. From these, nine phosphine complexes [(R3P)AuC equivalent to CR] with R = Ph or Cy were synthesised. Reactions between the phosphine gold acetylides [(Ph3P)AuC equivalent to CC(Me)(OH)Et] or [(Cy3P)AuC equivalent to CC(Me)(OH)Et] and the iron carbonyl cluster [Et4N][Fe4N(CO)(12)] gave both neutral [(R3P)AuFe4N(CO)(12)] and ionic compounds [(R3P)(2)Au][Fe4N(CO)(12)]. Reaction with the penta-iron cluster [Et4N][Fe5N(CO)(14)] afforded [(R3P)(2)Au][Fe5N(CO)(14)], [(R3P)(2)Au][Fe4N(CO)(12)] and [(R3P)AuFe4N(CO)(12)]. The gold-iron clusters were characterised with spectroscopic methods (IR, NMR and Mossbauer) and in the case Of [(Cy3P)AuFe4N(CO)(12)] a single-crystal X-ray analysis. (c) 2005 Elsevier B.V. All rights reserved.