Synthesis, reactivity, electrochemical behavior, and crystal structure of a family of multivalent metal carbido-carbonyl clusters based on the Rh10(C)2Au(4-6) framework

Laura Cherchi; Alessandro Fumagalli; Serena Fedi; Piero Zanello; Fabrizia Fabrizi De Biani; Franco Laschi; Luigi Garlaschelli; Piero Macchi; Angelo Sironi

doi:10.1021/ic201613j

Synthesis, reactivity, electrochemical behavior, and crystal structure of a family of multivalent metal carbido-carbonyl clusters based on the Rh10(C)2Au(4-6) framework

Inorg Chem. 2012 Sep 3;51(17):9171-80. doi: 10.1021/ic201613j. Epub 2012 Aug 21.

Authors

Laura Cherchi¹, Alessandro Fumagalli, Serena Fedi, Piero Zanello, Fabrizia Fabrizi De Biani, Franco Laschi, Luigi Garlaschelli, Piero Macchi, Angelo Sironi

Affiliation

¹ Dipartimento di Scienze Teoriche e Applicate, Università dell'Insubria, via J. H. Dunant 3, 21100 Varese, Italy.

PMID: 22909400
DOI: 10.1021/ic201613j

Abstract

Six metal carbido-carbonyl clusters have been isolated and recognized as members of a multivalent family based on the dioctahedral Rh(10)(C)(2) frame, with variable numbers of CO ligands, AuPPh(3) moieties, and anionic charge: [Rh(10)(C)(2)(CO)(x)(AuPPh(3))(y)](n-) (x = 18, 20; y = 4, 5, 6; n = 0, 1, 2). Anions [Rh(10)(C)(2)(CO)(18)(AuPPh(3))(4)](-) ([2](-)) and [Rh(10)(C)(2)(CO)(18)(AuPPh(3))(4)](2-) ([2](2-)) have been obtained by the reduction of [Rh(10)(C)(2)(CO)(18)(AuPPh(3))(4)] (2) under N(2), while [Rh(10)(C)(2)(CO)(18)(AuPPh(3))(5)](-) ([3](-)) was obtained from [Rh(10)(C)(2)(CO)(20)(AuPPh(3))(4)] (1) by reduction under a CO atmosphere. [3](-) can be better obtained by the addition of AuPPh(3)Cl to [2](2-). [Rh(10)(C)(2)(CO)(18)(AuPPh(3))(6)] (4) is obtained from [3](-) and 2 as well by the reduction and subsequent addition of AuPPh(3)Cl. The molecular structures of [2](2-) ([NBu(4)](+) salt), [3](-) ([NMe(4)](+) salt), and 4 have been determined by single-crystal X-ray diffraction. The redox activities of complexes 1, 2 and [3](-) have been investigated by electrochemical and electron paramagnetic resonance (EPR) techniques. The data from EPR spectroscopy have been accounted for by theoretical calculations.