Ferrocenyl‐Functionalized Tetranuclear Gold(I) and Gold(I)–Copper(I) Complexes Based on Tridentate Phosphanes

Abstract

Abstract Tetranuclear Au I –Fe II dimetallic and Au I –Cu I –Fe II trimetallic complexes bearing ferrocenyl (Fc) groups have been assembled by using two triphosphane ligands, namely, (PPh 2 CH 2 ) 2 PPh (dpmp) and (PPh 2 ) 3 CH (tppm). The compositions and structural type of the clusters are dependent on the stereochemistry of the P donor ligands. The complexes [tppmAu 3 Cu(C 2 R) 3 ]PF 6 [R = Fc ( 1 ) and 4‐C 6 H 4 ‐Fc ( 2 )] adopt a trigonal pyramidal {Au 3 Cu} arrangement of the coordinating metal core, whereas for the compounds with the linear triphosphane [Au 4 (dpmp) 2 (C 2 R) 2 ](PF 6 ) 2 [R = Fc ( 3 ) and 4‐C 6 H 4 ‐Fc ( 4 )], a planar rhomboidal {Au 4 } framework was found. Clusters 1 – 4 were characterized by NMR spectroscopy and ESI‐MS measurements. The solid‐state structures of 1 , 3 , and 4 have been determined by X‐ray crystallography. The electrochemical properties of 1 – 4 were studied and revealed redox processes attributed to the Fc functions. Oxidation of the Fc units in 1 , 2 , and 4 occurs independently. In 3 , an electron transfer process mediated by the {Au 4 } metal core was observed.