Coordination versus Insertion: On the Interaction of 5 d‐Transition Metal Carbonyl Clusters with Silver(I)

Abstract

AbstractThe title silver(I) complex salts [Ag{Re2(CO)10}{Re(CO)5}2]+[Al(ORF)4]− (AgRe4; ORF=‐OC(CF3)3) and [Ag{Ir4(CO)12}2]+[Al(ORF)4]− (AgIr8) form upon reaction of Ag+[Al(ORF)4]− and the transition metal carbonyls (TMCs) Re2(CO)10 and Ir4(CO)12 respectively. The solid‐state structure of the AgRe4 cluster shows an unexpected asymmetric coordination motif, wherein the silver(I) cation has inserted into the Re−Re bond of one Re2(CO)10 moiety, while the other dirhenium carbonyl coordinates only over one metal atom towards the silver(I) cation. The AgIr8 cluster is formed by the edge‐on coordination of two Ir4 tetrahedra and the silver cation in a D2 symmetric fashion with a torsion angle of 46.5°. QTAIM analysis shows bond paths between the silver atom and the nearby metal atoms in all cases, whereas only the non‐inserted Re2(CO)10 moiety shows additional bond paths between the carbonyl ligands and the silver cation. In addition, the insertion of the Ag+ cation into the Re−Re bond in Re2(CO)10 removes the bond path between the two rhenium atoms. The EDA‐NOCV analysis suggests an increase of the interaction energy between the silver(I) cation and the respective metal carbonyls from the metal centered transition metal carbonyl (TMC) donors W(CO)6<Re2(CO)10<Os3(CO)12<Ir4(CO)12. In all cases, the dominating orbital interaction is σ‐donation [TMC]→Ag+←[TMC].