Stable ‐ESiMe₃ Complexes of Cu^I and Ag^I (E=S, Se) with NHCs: Synthons in Ternary Nanocluster Assembly

Abstract

As a part of efforts to prepare new "metallachalcogenolate" precursors and develop their chemistry for the formation of ternary mixed-metal chalcogenide nanoclusters, two sets of thermally stable, N-heterocyclic carbene metal-chalcogenolate complexes of the general formula [(IPr)Ag-ESiMe3] (IPr=1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene; E=S, 1; Se, 2) and [(iPr2-bimy)Cu-ESiMe3]2 (iPr2-bimy=1,3-diisopropylbenzimidazolin-2-ylidene; E=S, 4; Se, 5) are reported. These are prepared from the reaction between the corresponding carbene metal acetate, [(IPr)AgOAc] and [(iPr-bimy)CuOAc] respectively, and E(SiMe3 )2 at low temperature. The reaction of [(IPr)Ag-ESiMe3] 1 with mercury(II) acetate affords the heterometallic complex [{(IPr)AgS}2Hg] 3 containing two (IPr)Ag-S(-) fragments bonded to a central Hg(II), representing a mixed mercury-silver sulfide complex. The reaction of [(iPr2-bimy)Cu-SSiMe3]2, which contains a smaller N-heterocyclic-carbene, with mercuric(II) acetate affords the high nuclearity cluster, [(iPr2-bimy)6Cu10S8Hg3]6. The new N-heterocyclic carbene metal-chalcogenolate complexes 1, 2, 4, 5 and the ternary mixed-metal chalcogenolate complex 3 and cluster 6 have been characterized by multinuclear NMR spectroscopy ((1)H and (13)C), elemental analysis and single-crystal X-ray diffraction.

Chalcogenido‐Dimethylgallates and ‐Indates DMPyr2[Me2M(μ2−E)]2 (M=Ga, In; E=S, Se): Building Blocks for Higher and Lower Order Chalcogenidoindates

“…Complexes containing silylchalcogenido ligands [M−E−SiMe 3 ] are attractive synthons for condensation reactions e. g. with heterometal acetates M'OAc in order to selectively synthesize heteronuclear linkages M−E−M’ by elimination of Me 3 SiOAc [11,15,22–24] . For a long time, only two structural motives with heavy silylchalcogenido ligands were known: the spirocyclic compounds [(Me 2 M) 6 E(ESiMe 3 ) 4 ] (M=Ga, In; E=S, Se), [25] and [ i Pr 3 PCu( μ 3 2 −ESiMe 3 )(InMe 3 )] (E=S, Se): [26] The latter is the addition product of Me 3 In and i Pr 3 PCuESiMe 3 .…”

Homoleptic Group 13 Trimethylsilylchalcogenolato Metalates [M(ESiMe3)4]− (M = Ga, In; E = S, Se): Metastable Precursors for Low-Temperature Syntheses of Chalcogenide-Based Materials

“…Ligands and Novel Homoleptic Metalates as Precursors for Binary Materials (Eq 1), 16,17 Clusters (Eq 2), 11,19,20 With 1−4 we have all Ga/In/S/Se combinations as binary metastable building blocks in hand. With the exception of 1 they could also be structurally characterized (Supporting Information).…”

“…A few heteroleptic neutral complexes containing the reactive trimethylsilylchalcogenolate moiety L x M(ESiMe 3 ) y (L = auxiliary ligand; E = S, Se, Te; M = Zn, 14−16 Cd, 17 Cu, 18,19 Ag, 19 Au, 20 Mn, 21 Co) 21 are known as versatile precursors for binary materials ME 0.5y and as starting materials for chalcogenide metal cluster synthesis. 11,14,18,20,22 This is attributed to the driving force behind the thermally inducible intra-or intermolecular elimination of volatile E(SiMe 3 ) 2 and the formation of the corresponding metal chalcogenides (Scheme 1, eq 1) 16,17 and the facile removability of the SiMe 3 moiety by compounds containing silicon affine nucleophiles X in the compound M′X (X = e. g. OAc) (Scheme 1, eq 2).…”

“…A few heteroleptic neutral complexes containing the reactive trimethylsilylchalcogenolate moiety L x M­(ESiMe 3 ) y (L = auxiliary ligand; E = S, Se, Te; M = Zn, − Cd, Cu, , Ag, Au, Mn, Co) are known as versatile precursors for binary materials ME 0.5 y and as starting materials for chalcogenide metal cluster synthesis. ,,,, This is attributed to the driving force behind the thermally inducible intra- or intermolecular elimination of volatile E­(SiMe 3 ) 2 and the formation of the corresponding metal chalcogenides (Scheme , eq 1) , and the facile removability of the SiMe 3 moiety by compounds containing silicon affine nucleophiles X in the compound M′X (X = e. g. OAc) (Scheme , eq 2). ,,− Among the known examples for ESiMe 3 -containing complexes, ,,,,,, only heteroleptic trimethylsilylchalcogenolate (E) complexes containing high-priced organogallium and organoindium units (R n M) have been described, namely four-membered rings such as [ t Bu 2 M­(μ 2 -SeSiMe 3 )] 2 , the spirocyclic M/E-heterocyclic compounds [(Me 2 M) 6 E­(ESiMe 3 ) 4 ], and the polynuclear compound [R 3 PCu­(μ 2 -ESiMe 3 )­MMe 3 ]; the last compound decomposes at room temperature . Furthermore, only one example of a homoleptic trimethylsilylchalcogenidometalate anion, namely [(tmeda)­Li] 2 [Mn­(SSiMe 3 ) 4 ], has been reported .…”

A Series of Homoleptic Linear Trimethylsilylchalcogenido Cuprates, Argentates and Aurates Cat[Me3SiE–M–ESiMe3] (M = Cu, Ag, Au; E = S, Se)

“…However, to date, mononuclear neutral compounds containing a coinage metal attached E–SiMe 3 group were made accessible only by applying strongly binding amine, phosphine, or N-heterocyclic carbene auxiliary ligands. While the phosphine compounds of the type [R 3 P–M–ESiMe 3 ] are quite difficult to handle, the NHC analogues [NHC–M–ESiMe 3 ] and related cyclic alkyl­(amino)­carbenes (CAAC) [CAAC–M–ESiMe 3 ] are of reasonable stability for using them in selective bottom-up syntheses of defined ternary clusters with tunable optical properties. ,, Finally, NHC masked coinage metal silylchalcogenido complexes have been used as precursors for the preparation of coinage metal chalcogenide materials M 2 E . These materials are receiving growing interest due to their negligible toxicity and their potential to act as e.g.…”