Silver(i) and thallium(i) cations as unsupported bridges between two metal bases

Abstract

Stirring Lewis-basic transition metal complexes with the salts M[BAr(Cl)4] (M = Ag, Tl; Ar(Cl) = 3,5-C6H3Cl2) resulted in the formation of diplatinum complexes [{(Cy3P)2Pt}2(μ-Ag)][BAr(Cl)4] (3) and [{(Cy3P)2Pt}2(μ-Tl)][BAr(Cl)4] (4) and the diiron compound [{(OC)3(Me3P)2Fe}2(μ-Ag)] (5) featuring bridging, unsupported metal cations. Their properties were investigated by multinuclear NMR spectroscopy, as well as X-ray diffraction and infrared measurements.

Syntheses and Structures of Ruthenium Complexes Containing a Ru‐H‐Tl Three‐Center–Two‐Electron Bond

“…Thelack of observable Tl-H couplings could be related to the reversible dissociation/ association of the Tl + ,which is supported by the fact that the 1 HNMR spectra of solutions prepared by mixing CpRuH-(PP) with less than one equivalent of TlPF 6 or by mixing [CpRu{h 2 -(H À Tl)}(PP)]PF 6 with CpRuH(PP) showed asingle hydride signal in the region between those of CpRuH(PP) and [CpRu{h 2 -(H À Tl)}(PP)]PF 6 .The result is not surprising as there are ample examples [34] that P-Tl couplings are not resolved in the NMR spectra of complexes containing both thallium and phosphine ligands for the same reason. Thelack of observable Tl-H couplings could be related to the reversible dissociation/ association of the Tl + ,which is supported by the fact that the 1 HNMR spectra of solutions prepared by mixing CpRuH-(PP) with less than one equivalent of TlPF 6 or by mixing [CpRu{h 2 -(H À Tl)}(PP)]PF 6 with CpRuH(PP) showed asingle hydride signal in the region between those of CpRuH(PP) and [CpRu{h 2 -(H À Tl)}(PP)]PF 6 .The result is not surprising as there are ample examples [34] that P-Tl couplings are not resolved in the NMR spectra of complexes containing both thallium and phosphine ligands for the same reason.…”

Reactions of Digallanes with p‐ and d‐Block Lewis Bases: Adducts, Bis(gallyl) Complexes, and Naked Ga+ as Ligand

“…The reactions forming 5 a and b clearly involve retention of—or disproportionation into—a mixed‐valence Ga I /Ga III situation. The ligation of the Ga + cation to Pt could be thought of as being analogous to the MOLPs formed between late transition metals and Group 11 cations; however, the implied monovalency of the Ga + cation suggests a more complicated bonding situation between the Pt and the Ga atoms, possibly involving the lone pair of electrons of the Ga + cation.…”

“…[8b,f] The remaining established synthetic routes to Ga 2 X 4 L 2 adducts include conventional reductive coupling of halogallane Lewis adducts ( Figure 1B and C) [7a, 8b] and an umber of unusual 1,3-additions of alkynes and allyl bromide to tetraaminodigallanes(4) ( Figure 1E,G). [8a,c,d] The limitedk nowledge of the chemistry of digallanes and our established interesti nm ultihalodiboranes(4), [2c] transitionmetal (TM) Lewis bases, [10] and the formation and cleavage of bondsb etween Group 13 elements,[4] awoke our interesti ne xploring the chemistry of digallanes with ar ange of Lewis bases,p articularly those based on carbon and platinum.S pecifically the latter have already provent ob ev ersatile bases for the formation of Lewis pairs with Group 13 electron acceptors. [10] Herein, we prepare ar ange of double carbene adducts of digallanes(4) from an existingd ouble digallane adduct and subsequently induce exchange reactions of their halide groups,e stablishing the feasibility of both base and halide-exchange reactions from digallane adducts.F urthermore, sources of digallium species are treated with transition-metal Lewis bases,l eadinga lternativelyt oo xidative addition products, species with monocoordinateG a + ligands, and an unusual ditopic metal-only Lewis pair (MOLP).…”

“…[10] Herein, we prepare ar ange of double carbene adducts of digallanes(4) from an existingd ouble digallane adduct and subsequently induce exchange reactions of their halide groups,e stablishing the feasibility of both base and halide-exchange reactions from digallane adducts.F urthermore, sources of digallium species are treated with transition-metal Lewis bases,l eadinga lternativelyt oo xidative addition products, species with monocoordinateG a + ligands, and an unusual ditopic metal-only Lewis pair (MOLP). [10]…”

Syntheses and Structures of Ruthenium Complexes Containing a Ru‐H‐Tl Three‐Center–Two‐Electron Bond

“…In the room-temperature 1 HNMR spectra, the expected Tl-H coupling was not resolved. Thelack of observable Tl-H couplings could be related to the reversible dissociation/ association of the Tl + ,which is supported by the fact that the 1 HNMR spectra of solutions prepared by mixing CpRuH-(PP) with less than one equivalent of TlPF 6 or by mixing [CpRu{h 2 -(H À Tl)}(PP)]PF 6 with CpRuH(PP) showed asingle hydride signal in the region between those of CpRuH(PP) and [CpRu{h 2 -(H À Tl)}(PP)]PF 6 .The result is not surprising as there are ample examples [34] that P-Tl couplings are not resolved in the NMR spectra of complexes containing both thallium and phosphine ligands for the same reason. [35] Scheme 2.…”