Close Correlation between Metal Oxidation States and Molecular Structures in a Cobalt–Gold Multinuclear Coordination System with Mixed D‐Penicillaminate and Tripodal Triphosphine

Abstract

A unique cobalt-gold coordination system, in which the oxidation states of the cobalt centers are closely correlated with the multinuclear molecular structures, is reported. This system contains a Co II 3 Au I 6 nonanuclear structure in [Co 3 {Au 3 (tdme)(D-pen-N,O,S) 3 } 2 ] ([2]) and a Co III Au I 3 tetranuclear structure in [Co{Au 3 (tdme)(D-pen-N,S) 3 }] ([3]) [tdme = 1,1,1-tris(diphenylphosphinomethyl)ethane, D-pen = D-[a]

Counter‐Anion‐Regulated Mixed‐Valency of Cobalt(II/III) Centers in a Metallosupramolecular Framework

“…[13,17,18] Single-crystal X-ray crystallography indicated that [1 Lnmc ](ClO 4 ) n crystallizes in ac ubic crystal system with the chiral space group F432 (Table S2), with aq uarter of the complex cation being crystallographicallyi ndependent. [13,19] As shown in [16] This is compatible with the magnetic measurementst hat showed the presence of high spin Co II and low spin Co III centers in a1 :1 ratio in [1 L-nmc ](ClO 4 ). In the crystal packing of [1 L-nmc ](ClO 4 ), 6c omplex cationsa re assembled to form as upramolecular octahedron of {[1 L-nmc ] + } 6 (Figure 2c), and the octahedra are closely packed in af cc lattice structure, as found in [1 D-pen ](ClO 4 ) 2 (Figure 2d).…”

“…The c M T value at 300 Kw as 2.46 cm 3 Kmol À1 ,w hichi sv ery similart ot he reported c M T value of 2.38 cm 3 Kmol À1 per one high-spin Co II center in [Co II 3 {Au 3 (tdme)(d-pen) 3 } 2 ]. [16] From the analysis including ligand-field parameters (d, e), spin-orbit coupling (l), orbital reductionf actor (k), temperature independentp aramagnetism (T.I.P), and mean-field interaction (zJ), the ratio of paramagnetic Co II to diamagnetic Co III in [1 L-nmc ](ClO 4 ) n was evaluated to be almost1:1 ( Figure S8, Table S1). [13,17,18] Single-crystal X-ray crystallography indicated that [1 Lnmc ](ClO 4 ) n crystallizes in ac ubic crystal system with the chiral space group F432 (Table S2), with aq uarter of the complex cation being crystallographicallyi ndependent.…”

Metallosupramolecular Structures Derived from a Series of Diphosphine-bridged Digold(I) Metalloligands with Terminald-Penicillamine

“…This strategy is a straightforward improvement regarding the diversity of metalloligands. In this section, we will briefly describe our very recent study on the coordination behavior of a simple monogold(I) metalloligand [Au(PPh 3 )( d ‐Hpen‐ S )] ([H 6 ]) and a tripod‐type trigold(I) metalloligand, [Au 3 (tdme)( d ‐Hpen‐ S ) 3 ] ([H 3 7 ]; tdme = 1,1,1‐tris(diphenylphosphinomethyl)ethane) to a cobalt(II) ion (Scheme ) 21,22…”

“…The oxidized complex, [Co 3 {Au 3 (tdme)( d ‐pen) 3 } 2 ] 3+ ([ 32 ] 3+ ), was finally obtained as a nitrate salt after treatment with ceric ammonium nitrate (CAN), which is one of the strongest oxidizing agents available (Figure d). X‐ray analysis revealed an unusually large structural distortion around the cobalt(III) center present in [ 32 ] 3+ relative to the dppe‐containing complex [ 25 ] 2+ and a simple trinuclear Au I Co III complex, [Co{Au(PPh 3 )( d ‐pen)} 2 ] + ([ 29 ] + ), which is derived from the monogold(I) metalloligand [H 6 ] 22. We noted that the averaged Co–S bond distances increased in the order [ 29 ] + < [ 25 ] 2+ < [ 32 ] 3+ , which parallels the order of their nuclearities.…”

“…The coordination mode of [Au 2 (dppx)( d ‐pen‐ S ) 2 ] 2– to second‐metal ions is categorized into three types: chelating, closed‐bridging, and extended‐bridging; these types will be discussed in terms of the alkyl chain length of the dppx linker (Figure ). The coordination behavior of monophosphine and triphosphine analogues, [Au(PPh 3 )( d ‐pen‐ S )] – ([ 6 ] – )21 and [Au 3 (tdme)( d ‐pen‐ S ) 3 ] 3– ([ 7 ] 3– ; tdme = 1,1,1‐tris(diphenylphosphinomethyl)ethane),22 will also be reviewed.…”