A hexanuclear gold carbonyl cluster

The hexanuclear gold carbonyl cluster [PPh(4)](2)[Au(6)(CF(3))(6)Br(2)(CO)(2)] (4) has been obtained by spontaneous self-assembly of the following independent units: CF(3)AuCO (1) and [PPh(4)][Br(AuCF(3))(2)] (3). The cyclo-Au(6) aggregate 4, in which the components are held together by unassisted, fairly strong aurophilic interactions (Au···Au ∼310 pm), exhibits a cyclohexane-like arrangement with chair conformation. These aurophilic interactions also result in significant ν(CO) lowering: from 2194 cm(–1) in the separate component 1 to 2171 cm(–1) in the mixed aggregate 4. Procedures to prepare the single-bridged dinuclear component 3 as well as the mononuclear derivative [PPh(4)][CF(3)AuBr] (2) are also reported.