Phosphor-1,1-Diselenolato Metal Complexes of Group 11 and 12

Abstract

Several copper and silver clusters containing diselenophosphate ligands such as tetranuclear [Cu{Se₂P(OR)₂}]₄, hexanuclear [Ag{Se₂P(OR)₂}]₆, octanuclear [Cu₈(μ₈-Se)}Se₂P(OR)₂}₆], [Ag₈(μ₈-Se)}Se₂P(OR)₂}₆], [Cu₈(μ₈-X)}Se₂P(OR)₂}₆](PF₆), [Ag₈(μ₈-X)}Se₂P(OR)₂}₆](PF₆), decanuclear [Ag₁₀(μ₁₀-Se)}Se₂P(OR)₂}₈], undecanuclear [Cu₁₁(μ₉-Se)(μ₃-X)₃}Se₂P(OR)₂}₆], [Ag₁₁(μ₉-Se)(μ₃-X)₃}Se₂P(OR)₂}₆], and dodecanuclear [Cu₁₂(P₂Se₆)}Se₂P(OR)₂}₈] have been isolated. All these clusters were well characterized in the solid-state and solution phase by elemental analysis, positive FAB mass spectrometry, multinuclear NMR (¹H, ³¹P, and ⁷⁷Se), and single crystal X-ray diffraction. In addition, tetranuclear zinc clusters [Zn₄(μ₄-Se){Se₂P(OPr)₂}₆], and [Zn₄(μ₄-O){Se₂P(OR)₂}₆] (R = Et, ⁱPr) also are synthesized and characterized. Solution studies of both [M{Se₂P(OEt)₂}₂]∞ and [M₂{Se₂P(OⁱPr)₂}₄] (M = Zn, Cd) which display a monomer-dimer equilibrium in solution were performed by VT ³¹P NMR in CD₂Cl₂.     

Eight‐Electron Silver and Mixed Gold/Silver Nanoclusters Stabilized by Selenium Donor Ligands

The first atomically and structurally precise silver‐nanoclusters stabilized by Se‐donor ligands, [Ag₂₀{Se₂P(OⁱPr)₂}₁₂] ( 3 ) and [Ag₂₁{Se₂P(OEt)₂}₁₂]⁺( 4 ), were isolated by ligand replacement reaction of [Ag₂₀{S₂P(Oⁱ Pr)₂}₁₂] ( 1 ) and [Ag₂₁{S₂P(Oⁱ Pr)₂}₁₂]⁺ ( 2 ), respectively. Furthermore, doping reactions of 4 with Au(PPh₃)Cl resulted in the formation of [AuAg₂₀{Se₂P(OEt)₂}₁₂]⁺ ( 5 ). Structures of 3 , 4 , and 5 were determined by single‐crystal X‐ray diffraction. The anatomy of cluster 3 with an Ag₂₀ core having C ₃ symmetry is very similar to that of its dithiophosphate analogue 1 . Clusters 4 and 5 exhibit an Ag₂₁ and Au@Ag₂₀ core of O_h symmetry composed of eight silver capping atoms in a cubic arrangement and encapsulating an Ag₁₃ and Au@Ag₁₂ centered icosahedron, respectively. Both ligand exchange and heteroatom doping result in significant changes in optical and emissive properties for chalcogen‐passivated silver nanoparticles, which have been theoretically confirmed as 8‐electron superatoms.     

Octanuclear Cu(I)‐dithiophosphates: An Efficient Catalyst System for N‐Arylation of Azoles,Amines, and Amides

The formation of a C‐N bond via the cross‐couplings of aryl iodides with azoles, aryl amine, and amides can be successfully achieved in decent yield by the utilization of both [Cu ₈(H){S₂P(OⁱPr)₂}₆]⁺ and [Cu₈{S₂P(OEt)₂}₆]²⁺ as the pre‐catalysts.     

Bis(diethoxyselenophosphinoyl) triselenide and bis(diisopropoxyselenophosphinoyl) diselenide

The title compounds, bis(diethoxyselenophosphinoyl) triselenide, [P(OEt)₂Se]Se₃[P(OEt)₂Se], and bis­(diisopropoxy­selenophosphinoyl) diselenide, [P(OⁱPr)₂Se]Se₂[P(OⁱPr)₂Se], comprise an Se₃ chain or an Se₂ chain bridging two (RO)₂PSe groups.     

Unified reciprocity of dithiophosphate by dichalcogenophosph(in)ate ligands on copper hydride nanoclusters via ligand exchange reaction

A structural study of ligand exchange on chalcogen‐passivated copper nanoclusters is far less developed. Herein, we report the synthesis of polyhydrido copper nanoclusters [Cu₂₀H₁₁{Se₂P(O ⁱBu)₂}₉] ( 2 ) passivated by Se‐donor ligands via ligand replacement reaction on [Cu₂₀H₁₁{S₂P(O ⁱPr)₂}₉] ( 1 ) with NH₄[Se₂P(O ⁱBu)₂]. In parallel to the synthesis of 2 , cluster [Cu₂₀H₁₁{S₂P(CH₂CH₂Ph)₂}₉] ( 4 ) was produced by the ligand exchange reaction on a new derivative of 1 , that is [Cu₂₀H₁₁{S₂P(O ⁿPr)₂}₉] ( 3 ). Solid state structures of both clusters 2 and 4 were unequivocally established by single‐crystal X‐ray diffraction studies and cluster 4 epitomizes exceptional case to preserve both the shape and size of the nanocluster during the course of ligand exchange. Structurally precise cluster 2 is the second example where the copper hydride nanocluster is stabilized by Se‐donor ligands. The anatomy of 2 can be visualized as a twisted cuboctahedral Cu₁₃ core, two triangular faces of which are capped by a Cu₆ cupola and a single Cu atom along the C₃ rotational axis.     

A Sulfide (Selenide)-Centered Nonanuclear Silver Cluster: A Distorted and Flexible Tricapped Trigonal Prismatic Ag<Subscript>9</Subscript> Framework

Two luminescent, monoanionic chalcogenide-centered nonanuclear silver clusters stabilized by dichalcogenophosphates were synthesized and fully characterized by various spectroscopies including multinuclear NMR and ESI-mass. Single crystal X-ray diffraction studies on both cluster anions, [Ag₉(S){S₂P(OEt)₂}₈]^?, 1, and [Ag₉(Se){Se₂P(OEt)₂}₈]^?, 2, reveal that the nine silver atoms form an extremely distorted tricapped trigonal prism, which has an encapsulating chalcogenide. The coordination geometry of the central chalcogenide appears to be monocapped trigonal prismatic, which was analyzed by DFT calculations. The origin of the yellow emission is assigned by TDDFT calculations to originate from a chalcogen (ligand + encapsulated) → silver charge transfer.     

Synthesen und Kristallstrukturen neuer chalkogenido‐verbrückter Niob‐Kupfer‐Cluster

Syntheses and Crystal Structures of Novel Chalcogenido‐bridged Niobium Copper Clusters In the presence of tertiary phosphines, the reaction of NbCl₅ and Copper(I) salts with Se(SiMe₃)₂ (E = S, Se) affords the new chalcogenido‐bridged niobium‐copper cluster compounds ( 1 ) and [NbCu₄Se₄Cl (PPh₃)₄] ( 2 ). Using E(R)SiMe₃ (E = S, Se, R = Ph, ⁿPr) instead of the bisilylated selenium species leads to the compounds [NbCu₂(SPh)₆(PMe₃)₂] ( 3 ), [NbCu₂(SPh)₆(PⁿPr₃)₂] ( 4 ), [NbCu₂(SePh)₆(PMe₃)₂] ( 5 ), [NbCu₂(SePh)₆(PⁿPr₃)₂] ( 6 ), [NbCu₂(SePh)₆(PⁱPr₃)₂] ( 7 ), [NbCu₂(SePh)₆(P^tBu₃)₂] ( 8 ), [NbCu₂(SePh)₆(PⁱPr₂Me)₂] ( 9 ), [NbCu₂(SePh)₆(PPhEt₂)₂] ( 10 ), [Nb₂Cu₂(SⁿPr)₈(PⁿPr₃)₂Cl₂] ( 11 ) and [Nb₂Cu₆(SⁿPr)₁₂(PⁱPr₃)₂Cl₄]·2 CH₃CN ( 12 ·2 CH₃CN). By reacting Cu^I salts and NbCl₅ with the monosilylated selenides Se(^tBu)SiMe₃ and Se(ⁱPr)SiMe₃ which have a weak Se–C bond the products [Nb₂Cu₆Se₆(PⁱPr₃)₆Cl₄] ( 13 ), [Nb₂Cu₄Se₂(SeⁱPr)₆(PⁿPr₃)₄Cl₂] ( 14 ) and [Nb₂Cu₆Se₂(SeⁱPr)₁₀(PEt₂Me)₂Cl₂]·DME ( 15 ) are formed which contain selenide as well as alkylselenolate ligands. The molecular structures of all of these new compounds were determined by single crystal X‐ray diffraction measurements.     

Structural studies of phosphor-1,1-diselenoato Mn(I) and Re(I) complexes

Mononuclear complexes of the type, M(CO)₄[Se₂P(OR)₂] (M = Mn, R = ⁱPr, 1a; Et, 1b; M = Re, R = ⁱPr, 3a; Et, 3b) can be prepared from either [-Se(Se)P(OⁱPr)₂]₂ (A) or [Se{-Se(Se)P(OEt)₂}₂] (B) with M(CO)₅Br. O,O′-dialkyl diselenophosphate ([(RO)₂PSe₂]^-, abbreviated as dsep) ligands generated from A and B act as a chelating ligand in these complexes. Upon refluxing in acetonitrile, these mononuclear complexes yield dinuclear complexes with a general formula of [M₂(CO)₆{Se₂P(OR)₂}₂] (M = Mn, R = ⁱPr, 2a; Et, 2b; M = Re, R = ⁱPr, 4a; Et, 4b). Dsep ligands display a triconnective, bimetallic bonding mode in the dinuclear compounds and this kind of connective pattern has never been identified in any phosphor-1,1-diselenoato metal complexes. Compounds 2b, 3b, and 4 are structurally characterized. Compounds 2b and 3b display weak, secondary Se?Se interactions in their lattices.     

Synthesis,Crystal Structures,and Thermolysis Studies of Heteronuclear Transition Metal Aluminum Alcoholates

Heteronuclear alcoholate complexes [M{Al(OiPr)₄}₂(bipy)] ( 2-M , M = Fe, Co, Ni, Cu, Zn) and [M{Al(OcHex)₄}₂(bipy)] ( 3-M , M = Fe, Co, Ni, Zn) are formed by adduct formation of [M{Al(OiPr)₄}₂] ( 1-M , M = Fe, Co, Ni, Cu, Zn) with 2,2'-bipyridine and transesterification reaction with cHexOAc. According to crystal structure analyses, in 2-M and 3-M the central transition metal ion M²⁺ is coordinated by two chelating Al(OR)₄^– moieties and one bipyridine ligand in an octahedral arrangement. Treating 1-Cu with 2,2'-bipyridine leads to a reduction process, whereat the intermediate [Cu{Al(OiPr)₄}(bipy)₂][Al(OiPr)₄] ( 4 ) could be structurally characterized. During conversion of the iso-propanolate ligands in 1-Cu to cyclohexanolate ligands, Cu²⁺ is reduced to Cu⁺ forming [Cu{Al(O^cHex)₄}(py)₂] ( 5 ). UV/Vis-spectra and results of thermolysis studies by TG/DTA-MS are reported.     

The influence of alkane spacer of bis(diphenylphosphino)alkanes on the nuclearity of silver(I): Syntheses and structures of P,P′-bridged clusters and coordination polymers involving dithiophosphates

The effect of the length of alkane spacer in diphosphines on the nuclearity of Ag(I) complexes containing dialkyl dithiophosphates (dtp) ligands has been investigated. 1,1-Bis(diphenylphosphino)methane (dppm) yielded tetranuclear [Ag₄(dppm)₂{S₂P(OEt)₂}₄] (1), [Ag₄(dppm)₂{S₂P(OⁱPr)₂}₄] (3), trinuclear [Ag₃(dppm)₃{S₂P(OEt)₂}₂](PF₆) (2), and a dinuclear [Ag₂(dppm)₂{S₂P(OⁱPr)}](PF₆) (4). The increase in spacer length from one methylene in dppm to two in 1,2-bis(diphenylphosphino)ethane (dppe) resulted in the formation of polymeric, [Ag(dppe){S₂P(OR)₂}]_∞ (R = Et, 5a and 5a′; ⁱPr, 5b), and [Ag₄(μ₃-Cl)(dppe)_1.5{S₂P(OR)₂}₃]_∞ (R = Et, 6a; ⁱPr, 6b). Compounds 5a, 5b, 6a and 6b were reported earlier [C.W. Liu, B.-J. Liaw, L.-S. Liou, J.-C. Wang, Chem. Commun. (2005) 1983]. Further increase in the chain length to four methylene units in 1,4-bis(diphenylphosphino)butane (dppb) yielded dppb-bridged polymers, [Ag(dppb){S₂P(OEt)₂}]_∞ (7) and [Ag₂(dppb){S₂P(OEt)₂}₂]_∞ (8). In all the polynuclear compounds, diphosphines acted as P,P′-bridging ligands, while the dtp ligands (S,S′-donors) adopted varieties of coordination patterns: S,S′-chelating (5, 7), S,S′-bridging (4), bimetallic-triconnective, μ₂:η²,η¹ (1, 3, 8), bimetallic-diconnective, μ₂:η² (2, 3) and trimetallic-triconnective, μ₃:η²,η¹ (6). Some of the complexes exhibit argentophilicity with Ag?Ag distances in the range, 2.918-3.360 Å. Concomitant bridging of two silver atoms either by dppm and dtp ligands (1, 3 and 4) or two dtp ligands (8) lead to close silver-silver contacts. The diphosphines (dppe and dppb) with longer spacer appeared to favor 1D or 2D polymers due to the flexibility of the spacer within the diphosphine unit by adopting anti conformation as opposed to syn conformation of the dppm linker is revealed in complexes.     

Hydride-containing 2-Electron Pd/Cu Superatoms as Catalysts for Efficient Electrochemical Hydrogen Evolution

The first hydride-containing 2-electron palladium/copper alloys, [PdHCu₁₁{S₂P(OⁱPr)₂}₆(C≡CPh)₄] ( PdHCu₁₁ ) and [PdHCu₁₂{S₂P(OⁱPr)₂}₅{S₂PO(OⁱPr)} (C≡CPh)₄] ( PdHCu₁₂ ), are synthesized from the reaction of [PdH₂Cu₁₄{S₂P(OⁱPr)₂}₆(C≡CPh)₆] ( PdH₂Cu₁₄ ) with trifluoroacetic acid (TFA). X-ray diffraction reveals that the PdHCu₁₁ and PdHCu₁₂ kernels consist of a central PdH unit encapsulated within a vertex-missing Cu₁₁ cuboctahedron and complete Cu₁₂ cuboctahedron, respectively. DFT calculations indicate that both PdHCu₁₁ and PdHCu₁₂ can be considered as axially-distorted 2-electron superatoms. PdHCu₁₁ shows excellent HER activity, unprecedented within metal nanoclusters, with an onset potential of −0.05 V (at 10 mA cm⁻²), a Tafel slope of 40 mV dec⁻¹, and consistent HER activity during 1000 cycles in 0.5 M H₂SO₄. Our study suggests that the accessible central Pd site is the key to HER activity and may provide guidelines for correlating catalyst structures and HER activity.     

Identification of an Eight-Electron Superatomic Cluster and Its Alloy in One Co-crystal Structure

Herein we report a crystal structure of [Au_0.5Ag_0.5@Ag₂₀{S₂P(OⁱPr)₂}₁₂](PF₆) [Cl@Ag₈{S₂P(OⁱPr)₂}₆](PF₆) (1), which compositions were supported by positive-mode electrospray ionization mass spectrometry. The structural elucidation indicates that the encapsulated atom of an Ag₁₃ the entered icosahedron can be replaced by a gold atom. Surprisingly, the capping Ag atoms on the surface of an icosahedron in 1 reveal a different arrangement from the previously reported [Ag₂₁{S₂P(OⁱPr)₂}₁₂](PF₆) of C₃ symmetry. Besides, the preference for the central silver atom being oxidized by Au(I) is rationalized by the DFT calculations on three different computed [AuAg₂₀{S₂PH₂}₁₂]⁺ models having C₁, C₃, and T symmetry, respectively.     

Cobalt(II) Complexes with N‐Thioacylamidophosphates and 2,2′‐Bipyridyl and 1,10‐Phenathroline. Crystal Structures,Solution 1H NMR Spectral and Magnetic Properties

Structure and magnetic properties of N‐diisopropoxyphosphorylthiobenzamide PhC(S)‐N(H)‐P(O)(OiPr)₂ ( HL^I ) and N‐diisopropoxyphosphoryl‐N′‐phenylthiocarbamide PhN(H)‐C(S)‐N(H)‐P(O)(OiPr)₂ ( HL^II ) complexes with the Co^II cation of formulas [Co{PhC(S)‐N‐P(O)(OiPr)₂}₂] ( 1 ), [Co{PhN(H)‐C(S)‐N‐P(O)(OiPr)₂}₂] ( 2 ), [Co{PhC(S)‐N(H)‐P(O)(OiPr)₂}₂{PhC(S)‐N‐P(O)(OiPr)₂}₂] ( 1a ) and [Co{PhC(S)‐N‐P(O)(OiPr)₂}₂}(2,2′‐bipy)] ( 3 ), [Co{PhC(S)‐N‐P(O)(OiPr)₂}₂(1,10‐phen)] ( 4 ), [Co{PhN(H)‐C(S)‐N‐P(O)(OiPr)₂}₂(2,2′‐bipy)] ( 5 ), [Co{PhN(H)‐C(S)‐N‐P(O)(OiPr)₂}₂(1,10‐phen)] ( 6 ) were investigated. Paramagnetic shifts in the ¹H NMR spectrum were observed for high‐spin Co^II complexes with HL^I,II , incorporating the S‐C‐N‐P‐O chelate moiety and two aromatic chelate ligands. Investigation of the thermal dependence of the magnetic susceptibility has shown that the extended materials 1‐2 and 6 show ferromagnetic exchange between distorted tetrahedral ( 1 , 2 ) or octahedral ( 1a , 6 ) metal atoms whereas 3 and 5 show antiferromagnetic properties. Compound 4 behaves as a spin‐canted ferromagnet, an antiferromagnetic ordering taking place below a critical temperature, T_c = 115 K. Complexes 1 and 1a were investigated by single crystal X‐ray diffraction. The cobalt(II) atom in complex 1 resides a distorted tetrahedral O₂S₂ environment formed by the C=S sulfur atoms and the P=O oxygen atoms of two deprotonated ligands. Complex 1a has a tetragonal‐bipyramidal structure, Co(O^ax)₂(O^eq)₂(S^eq)₂, and two neutral ligand molecules are coordinated in the axial positions through the oxygen atoms of the P=O groups. The base of the bipyramid is formed by two anionic ligands in the typical 1,5‐O,S coordination mode. The ligands are in a trans configuration.     

Crystal Structure,Photophysical Properties,and Theoretical Investigation of Extremely Distorted Pentacapped Trigonal-Prismatic Undecasilver Clusters

A new cluster family of the type [Ag₁₁(S){S₂P(OR)₂}₈]⁺ (R = Et, Pr, ⁱPr) has been synthesized and characterized as their hexafluorophosphate salts. These compounds are the first silver dithiophosph(in)ato complexes exhibiting photoluminescence at ambient temperature. Their unprecedented skeletal structure describes a very distorted pentacapped trigonal-prismatic polyhedron. Geometry optimizations by DFT calculations on the R = H model reproduce the same structural arrangement in the ground state. Its electronic structure exhibits a low-lying LUMO with a large Ag(5s/5p) character whereas the highest occupied levels have a major contribution from the ligand sulfur lone pairs. The above-mentioned orbitals are shown to be responsible for the optical absorption and emission properties of these compounds.     

T-symmetric 40-nucleus silver clusters assembled by hetero-anions

We report two anion-templated Ag₄₀ clusters, [Ag₄₀(E)₄(SO₄){S₂P(OEt)₂}₂₄](PF₆)₆ (E = S, 1 ; Se, 2 ). The anionic templates were generated in situ from the decomposition of dithiophosphate (dtp) ligands. The extrusion of sulfur undergoes disproportionation reactions to generate sulfide and sulfate anions, which provide the source of templates in the subsequent cluster assembly reactions. Two Ag₄₀ clusters display high similarity in their structures. The sulfide (selenide) anions and the central sulfate anion reveal a six-coordinate and a rare dodecametallic dodecaconnective pattern, respectively. Four near-equivalent [Ag₁₀(E){S₂P(OEt)₂}₆]²⁺ motifs were assembled via the connection of central sulfate anion to construct Ag₄₀ clusters. The cluster cation, [Ag₄₀(E)₄(SO₄){S₂P(OEt)₂}₂₄]⁶⁺, displayed in T symmetry, is unprecedented in anion-templated silver clusters.     

Diselenophosphate‐Induced Conversion of an Achiral [Cu20H11{S2P(OiPr)2}9] into a Chiral [Cu20H11{Se2P(OiPr)2}9] Polyhydrido Nanocluster

A polyhydrido copper nanocluster, [Cu₂₀H₁₁{Se₂P(OiPr)₂}₉] ( 2_H ), which exhibits an intrinsically chiral inorganic core of C₃ symmetry, was synthesized from achiral [Cu₂₀H₁₁{S₂P(OiPr)₂}₉] ( 1_H ) of C_3h symmetry by a ligand‐exchange method. The structure has a distorted cuboctahedral Cu₁₃ core, two triangular faces of which are capped along the C₃ axis, one by a Cu₆ cupola and the other by a single Cu atom. The Cu₂₀ framework is further stabilized by 9 diselenophosphate and 11 hydride ligands. The number of hydride, phosphorus, and selenium resonances and their splitting patterns in multinuclear NMR spectra of 2_H indicate that the chiral Cu₂₀H₁₁ core retains its C₃ symmetry in solution. The 11 hydride ligands were located by neutron diffraction experiments and shown to be capping μ₃‐H and interstitial μ₅‐H ligands (in square‐pyramidal and trigonal‐bipyramidal cavities), as supported by DFT calculations on [Cu₂₀H₁₁(Se₂PH₂)₉] ( 2_H′ ) as a simplified model.     

Münzmetallcluster mit verbrückenden Imido‐ und Amidoliganden: [{Li(dme)3}4][Cu18(NPh)11] und [Ag6(NHPh)4(PnPr3)6Cl2]

Copper and Silver Clusters with Bridging Imido and Amido Ligands From the reactions of copper and silver chloride with tertiary phosphines and lithiated aniline the compounds [{Li(dme)₃}₄][Cu₁₈(NPh)₁₁] ( 1 ) and [Ag₆(NHPh)₄(PⁿPr₃)₆Cl₂] ( 2 ) were obtained. The structure of the anion in 1 is closely related to the structures of the reported clusters [Cu₁₂(NPh)₈]^4– [1] and [Cu₂₄(NPh)₁₄]^4– [2]: 1 represents the third phenyl imido bridged copper cluster which contains parallel Cu₃‐ and Cu₆‐planes. The dimeric compound 2 consists of two Ag₃ units with bridging phenyl amido ligands. Two chloride and six phosphine ligands complete the ligand sphere and shield the metal core effectively.     

THE METASTABLE PARTIALLY POSITIVELY CHARGED Se6 MOLECULE: PREPARATION,CHARACTERISATION AND X-RAY CRYSTAL STRUCTURE OF [Ag2(Se6)(SO2)2][Sb(OTeF5)6]2, [Ag2Se6][AsF6]2 AND [AgSe6][Ag2(SbF6)3]

Reactions designed to give Se₆[Sb(OTeF₅)₆]₂ by the reaction of Se₂Br₂, 4Se, and 2Ag[Sb(OTeF₅)₆] lead to products that include [Ag₂(Se₆)(SO₂)₂][Sb(OTeF₅)₆]₂(1). The distorted cubic (Ag₂Se₆ ²⁺) _n consists of a Se₆ molecule bicapped by two silver cations (local D_3d sym.). Reactions of AgMX₆ (M = As, Sb) with selenium in liquid SO₂ yielded crystals of [Ag₂Se₆][AsF₆]₂ (2) and [AgSe₆][Ag₂(SbF₆)₃] (3). Both salts contain stacked arrays of [AgSe₆]⁺ half-sandwich cationic units. [Ag₂Se₆][AsF₆]₂ in addition contains stronger, linear Se─Ag─Se horizontal linkages between the vertically stacked cationic columns. [AgSe₆][Ag₂(SbF₆)₃] features a remarkable three-dimensional [Ag₂(SbF₆)₃]^? anion held together by strong Sb─F···Ag contacts between component Ag⁺ and SbF₆ ^? ions. Hexagonal channels through this honeycomb-like anion are filled by the stacked [AgSe₆ ⁺]_x.     

Ligand metalation in an iridiumtris(diisopropylphosphinomethyl)borato complex: Synthesis, molecular structure and reactivity

The reaction of [IrCl(dmso)₃] with trisphosphinomethylborato ligand Li(THF){PhB(CH₂PⁱPr₂)₃} at room temperature results in intramolecular C-H activation of one of the ⁱPr substituents affording two diastereomers of cyclometalated iridium(III) complex [Ir(H)(dmso){PhB(CH₂PⁱPr₂)₂(CH₂PⁱPrCHMeCH₂)}] (1) in high yield in approximately equimolar ratio. NMR spectroscopic characterization indicates that only the diastereomers with the hydride ligand in cis position with respect to the metalacyclic phosphorous atom are formed as confirmed by single crystal X-ray diffraction. Facile ring opening with H₂ at room temperature gives dihydride [Ir(H)₂(dmso){PhB(CH₂PⁱPr₂)₃}] (2). However, C-H activation of benzene was not observed.