Dicoordinate Copper(I) Silanechalcogenolates

Abstract

The copper silanechalcogenolates tBu3PCuESiPh3 (1, E = O; 2, E = S; 3, E = Se) were prepared from the reaction of [tBu3PCu(CH3CN)3]BF4 with [Ph3SiELi(THF)2]2 in acetonitrile. The compounds were obtained as colorless, crystalline, but thermally labile solids. X-ray crystallography shows that complexes 1-3 are monomeric in the solid state with no Cu...Cu interactions. The Cu atoms have either a linear or a near-linear coordination geometry in all three complexes. Interestingly, the O atom in complex 1 is also linear, which is in contrast to the highly bent S (2) and Se analogues (3). Density functional theory calculations suggest that both the linear geometry of 1 and an associated extremely short Cu-O distance [1.769(4) A] are not the result of pi delocalization but are the result of a fine balance of electrostatic interaction and Pauli repulsion.

Mixed-Valence Manganese Carbonyl Complexes with Supersilyl Thiolate Ligands: [(OC)4Mn(μ-SSitBu3)2Mn(THF)X] (X = Br, SSitBu3) and Na(THF)6[(OC)3Mn(μ-SSitBu3)3MnSSitBu3]

“…The thermal ellipsoid of S2 (from the terminally bound thiolate) is fairly small, indicating that the Si−S−Mn unit does not deviate from linearity. This is significant, because there are a very limited number of transition-metal complexes of silyl or alkyl chalcogenolates with linear coordination . It has been postulated in the literature that chalcogenolate ligands can act as six-electron donors (analogous to Cp) by donating two σ and four π electrons. , The prerequisite for this type of donation, however, is linear coordination, which is rarely observed.…”

Decomposition Cascades of Dicoordinate Copper(I) Chalcogenides

“…Interestingly, the O atom in complex 1 is also linear, which is in contrast to the highly bent S and Se analogs, compounds 2 and 3, respectively. [10] Our initial calculations on H 3 PCuESiH 3 model compounds have indicated that the unusual geometry of the oxygen compound 1 is not caused by intermolecular orbital interactions such as extended π-delocalization, but are the result of a fine balance of electrostatic interaction and Pauli repulsion. [11] In the last section of this work, we will address the unusual solid-state structure of tBu 3 PCuESiPh 3 (1a) in more detail.…”

“…[9] Recently, we reported the synthesis and characterization of the first triad of monomeric dicoordinate copper(I) chalcogenide complexes tBu 3 PCuESiPh 3 (1, E = O; 2, E = S; 3, E = Se). [10] The X-ray analyses of the copper silylchalcogen-composition profile. Thermal decomposition is not likely to produce copper chalcogenide units CuE, but elemental copper Cu instead.…”

Synthesis and Structures of [LCu(I)(SSiiPr3)] (L = triphos, carbene) and Related Compounds

“…A related compound, [(IPr)Cu(SSiMe 3 )], has been very recently reported in separate work by Corrigan 18 and Hillhouse. 19 Two-coordinate copper(I) silylthiolate complexes are rather rare, with the only other examples being [(Ph 3 SiS)-Cu(P t Bu 3 )], 20 [(TripS)Cu(SSiPh 3 )] 1− (Trip = triptycyl), 21 and homoleptic [(Ph 3 SiS) 2 Cu] 1− . 7 The 2.1336(4) Å Cu−S bond length in 3 (Table 2) is indistinguishable from the corresponding value in [(IPr)Cu(SSiMe 3 )] (2.133(1) Å) but modestly shorter than the Cu−S bond distance in [(Ph 3 SiS)Cu(P t Bu 3 )], 2.1578(11) Å, which may be attributed to a smaller trans influence for IMes as compared to the highly basic P t Bu 3 ligand.…”