The Structure of Hydrotris(pyrazolyl)boratothallium(I)

The title compound crystallizes in the monoclinic space group P2₁ with a = 7.928(6), b = 9.306(4), c = 17.16(2) Å, β = 92.06(8)°, V = 1265(2) ų, Z = 2, D_calc = 2.191 g cm^–3. From two independent molecular units, metal-ligand strands are formed based on electrostatic interactions between the thallium centers and pyrazolyl π manifolds from neighboring molecules.     

A Manganese(II) Coordination Polymer with Ditopic Bis(pyrazol‐1‐yl)borate Bridges

The synthesis and characterization of the ditopic bis(pyrazol‐1‐yl)borate ligand Li₂[p‐C₆H₄(B(C₆F₅)pz₂)₂] is reported (pz = pyrazol‐1‐yl). Compared to the corresponding t‐butyl derivative Li₂[p‐C₆H₄(B(t‐Bu)pz₂)₂], the C₆F₅‐substituted scorpionate is significantly more stable towards hydrolysis. Reaction of Li₂[p‐C₆H₄(B(C₆F₅)pz₂)₂] with two equivalents of MnCl₂ leads to the formation of coordination polymers {(MnCl₂)₂(Li(THF)₃)₂[p‐C₆H₄(B(C₆F₅)pz₂)₂]}_∞ featuring penta‐coordinate Mn^II ions chelated by one bis(pyrazol‐1‐yl)borate fragment and further bonded to three chloride ions. Two of the three chloride ions are also coordinated to a neighbouring Mn^II ion; the third chloro ligand is shared between the Mn^II centre and a Li(THF)₃ moiety.     

Synthesis,Characterization, and Crystal Structure of Thallium(I) Complex containing Monodeprotonated 2,6‐Pyridinedicarboxylic Acid

The reaction of an ethanolic solution 2,6‐pyridinedicarboxylic acid ( 1 , LH₂) with TlNO₃ in the presence of triethylamine led to the coordination polymer [Tl(LH)]_n ( 2 ). The complex was characterized by elemental analysis, IR spectroscopy and single‐crystal X‐ray diffraction. Crystal data for 2 at –80 °C: monoclinic, space group I2/a, a = 696.1(1), b = 1190.6(2), c = 931.0(2) pm, β = 103.28(1)°, Z = 4, R₁ = 0.0256.     

Unusual Coordination Modes of Tris(pyrazol‐1‐yl)borates: Synthesis and Solid State Structures of Sodium[(dimethylamino)tris(pyrazol‐1‐yl)borate], Potassium[(dimethylamino)tris(pyrazol‐1‐yl)borate], and Potassium[phenyltris(pyrazol‐1‐yl)borate]

We report the optimized syntheses and the solid state structures of the alkali metal tris(pyrazol‐1‐yl)borates M[Me₂NBpz₃] (M = Na⁺ ( 1 ), K⁺ ( 2 ); pz = pyrazol‐1‐yl) and K[PhBpz₃] ( 3 ). Even though 1 and 2 consist of polymeric chains in the solid state, it is possible to identify subunits where the [Me₂NBpz₃]^? ion acts as tridentate ligand towards Na⁺ and K⁺ and binds via two of its pyrazolyl rings and its dimethylamino nitrogen atom (κ³N_pz,N_pz,N_NMe). In 3 , the ligand [PhBpz₃]^? employs two pyrazolyl donors and the π‐face of its phenyl substituent for potassium coordination (κ³N,N,C).     

Hydrotris(1,2,4‐triazolyl)borato Complexes with the Main Group Elements Ca,Sr, and Pb – Unexpectedly Bent ML2 Structures and a Stereochemically Inactive Lone Pair at Lead(II)

The coordination of the modified poly(azolyl)borato ligand hydrotris(1,2,4‐triazolyl)borato (L) with main group metals leads to complexes with coordination numbers of eight and the formula [CaL₂(H₂O)₂], [SrL₂(H₂O)₂], and [PbL₂(H₂O)₂]. The two L ligands coordinate in a “bent” arrangement to allow for the coordination of the two aqua ligands. This is in sharp contrast to six‐coordinated, pseudo‐octahedral CaTp₂ and PbTp₂ complexes [Tp = hydrotris(pyrazolyl)borato]. The calcium, strontium, and lead complexes are isostructural. No stereochemical lone pair activity is evident in [PbL₂(H₂O)₂]. Two additional water molecules of crystallization complete the crystal structure of [CaL₂(H₂O)₂] · 2 H₂O and [PbL₂(H₂O)₂] · 2 H₂O. In the synthesis of [PbL₂(H₂O)₂] an intermediate of the form [Pb(μ₃‐L)(NO₃)H₂O] could isolated and structurally characterized. There, the lead(II) center is seven coordinated with a presumably stereochemically active lone pair. Long M–L bonds argue for a more ionic bonding to the modified tris(triazolyl)borato ligand when compared to analogous M–Tp complexes.     

A Molecular Barium Hydrido Complex Stabilized by a Super‐Bulky Hydrotris(pyrazolyl)borate Ligand

Hydrogenolysis of the scorpionate‐supported barium alkyl complex (Tp^Ad,iPr)Ba[CH(SiMe₃)₂](THF) (Tp^Ad,iPr=hydrotris(3‐adamantyl‐5‐isopropyl‐pyrazolyl)borate) afforded the dinuclear barium hydrido complex [(Tp^Ad,iPr)Ba(μ‐H)]₂ ( 2 ), which was characterized by NMR spectroscopy and single‐crystal X‐ray analysis. Exposure of 2 with 1 atm of CO resulted in a reductive coupling process to form the cis‐ethendiolate dianion ( 3 ). Reaction of 2 with one equivalent of PhC≡C−C≡CPh gave barium 1,4‐diphenyl‐2‐butyne‐1,4‐diyl complex {[(Tp^Ad,iPr)Ba]₂(PhCH−C≡C−CHPh) ( 4 ).     

Synthesis and Crystal Structure of a New Silver(I) Complex

The reaction of 4-amino-6-methyl-1,2,4-triazine-3(2 H)-thione-5-one (AMTTO) with silver(I) nitrate in methanol gives the complex [Ag(AMTTO)₂]NO₃ ( 1 ). 1 was characterized by IR and ¹³C NMR spectroscopy and by an X-ray structure analysis [space group C2/c, Z = 4, lattice dimensions at –80 °C: a = 1306.7(2), b = 1139.0(2), c = 1089.2(1) pm, β = 94.54(1)°, R₁ = 0.0294]. The cation possesses a highly distorted linear coordination sphere in the solid state.     

Synthesis and Chloride Affinity of Sterically Demanding Ditopic Lithium Bis(pyrazol‐1‐yl)borates

The synthesis and full characterization of the sterically demanding ditopic lithium bis(pyrazol‐1‐yl)borates Li₂[p‐C₆H₄(B(Ph)pz^R₂)₂] is reported (pz^R = 3‐phenylpyrazol‐1‐yl ( 3 ^Ph), 3‐t‐butylpyrazol‐1‐yl ( 3 ^tBu)). Compound 3 ^Ph crystallizes from THF as THF‐adduct 3 ^Ph(THF)₄ which features a straight conformation with a long Li···Li distance of 12.68(1) Å. Compound 3 ^tBu was found to function as efficient and selective scavenger of chloride ions. In the presence of LiCl it forms anionic complexes [ 3 ^tBuCl]⁻ with a central Li‐Cl‐Li core (Li···Li = 3.75(1) Å).     

Characterization of Thallium(I) Saccharinate: an unprecedented Coordination of the Saccharinate Ligand

The crystal structure of [Tl₂(sac)₂(H₂O)]_n (sac = saccharinate anion) has been solved using single crystal X‐ray diffraction. It crystallizes in the triclinic space group P 1 with Z = 2 and presents a polymeric structure formed by two saccharinate anions, one water molecule and two chemically different Tl^I cations, one 8‐coordinate and the other 5‐coordinate. Saccharinate shows an unprecedented coordination behavior as it acts as chelating ligand through its N and carbonyl O atoms with the N atom interacting simultaneously with both metal centers, and participation of sulphonyl oxygen atoms in bonding. The most important features of the IR spectrum of the complex are discussed on the basis of the structural peculiarities.     

[PdCl(TeMe2)3](BArF) – The First Structurally Characterized Palladium(II) Complex with TeMe2 Ligands

[PdCl(TeMe₂)₃]BAr^F ( 4 ) forms as the major tellurium containing product from the reaction of [(4‐Mebti)PdCl] with TeMe₂ and Na(BAr^F) and is isolated by crystallization from the reaction mixture. At ?20 °C, the compound forms orange columns from toluene/pentane, space group , with Z = 2. In the solid, the cationic [PdCl(TeMe₂)₃]⁺ complex ions show a non‐planar PdClTe₃ coordination unit and are associated to dimers via weak Pd···Te interactions.     

Copper(I) complexes with fluorinated hydrotris(pyrazolyl)borate: Influence of electronic effects on their structure,physicochemical properties,and reactivity

Copper(I) coordination complexes of the anionic fluorinated ligand, hydrotris(3-trifluoromethyl-5-methyl-1-pyrazolyl)borate (L0f⁻), i.e. the copper(I) carbonyl complex, [Cu^I(L0f)(CO)] (1), the copper(I) triphenylphosphine complex, [Cu^I(L0f)(PPh₃)] (2), the copper(I) acetonitrile complex, [Cu^I(L0f)(NCMe)] (3), and the corresponding copper(I) triphenylphosphine complex with hydrotris(3,5-diisopropyl-1-pyrazolyl)-borate anion (L1⁻), i.e. [Cu^I(L1)(PPh₃)] (4), were synthesized in order to investigate the influence of the electron-withdrawing groups on the pyrazolyl rings. The structures of complexes 1, 2, and 4 were determined by X-ray crystallography. While X-ray crystallography did not show definitive trends in terms of copper(I) atom geometry, the clear influence of the electronic structure of the pyrazolyl rings is observed by spectroscopic techniques, namely, IR and multinuclear NMR spectroscopy. Finally, the relative stability of the copper(I) complexes is discussed.     

The Structure of the “Third‐Generation” Tris(pyrazolyl)borate Caesium Salt p‐BrC6H4TpCs

Slow crystallisation at lowered temperature yielded crystals of the “third‐generation” tris(pyrazolyl)borate transfer agent p‐BrC₆H₄TpCs (Tp′Cs) 1 (triclinic; P$\bar{1}$ ; a = 8.540(4), b = 15.045(6), c = 15.879(7) Å; α = 65.853(8), β = 88.457(8), γ = 75.056(8)°; V = 1791.4(13) Å³; Z = 4). The central caesium ion in 1 interacts with three individual p‐BrC₆H₄Tp ligands in two different chelating fashions.In particular, κ¹‐N‐coordination and η⁵‐π‐coordination of pyrazole moieties as well as η⁶‐π‐coordination of the p‐BrC₆H₄ substituent are observed. Further, comparable coordination of neighbouring caesium ions leads to the formation of polymeric structures connected by two bridging modes.     

π‐Complexes of Copper(I) Ionic Salts: Synthesis and Crystal Structure of (4‐Allylthiosemicarbazide)(sulfamato)copper(I) and Bis(4‐allylthiosemicarbazide)(sulfato‐O)dicopper(I)

Single crystals of [Cu(ATSC)]NH₂SO₃ ( 1 ) (ATSC –4‐allylthiosemicarbazide) were obtained by electrochemical synthesis using alternating current. Compound ( 1 ) crystallizes in P2₁2₁2₁ sp. gr., a = 6.8284(2), b = 9.3054(3), c = 16.1576(11) Å, Z = 4. ATSC moiety acts as tetradentate ligand, chelating two symmetrically related copper atoms. The Cu atom possesses trigonal pyramidal coordination, formed by two sulphur atoms (one of them at the apical position), nitrogen atom and C=C bond. Sulfamate anion is associated via hydrogen bonds. By slow hydrolysis of 1 crystals of [Cu₂(ATSC)₂]SO₄ ( 2 ) were obtained: P 1 sp. gr., a = 9.526(2), b = 12.687(2), c = 14.7340(10) Å, α = 95.119(10), β = 89.903(12), γ = 109.113(14)°, Z = 4. The asymmetric unit of 2 contains two formula units, which are related by pseudosymmetry via a glide plane a. One half of four ATSC molecules act as in 1 , the rest as tridentate ligands, which coordinate the two copper atoms in apical positions with sulfate anions. This Cu–S coordination was to date unknown. The structure of the ATSC ligands contributes to the unexpected competitiveness of C=bond in the coordination sphere of Cu^I inspite of strong donor atoms.     

两个半夹心型聚吡唑硼酸盐羧酸钴配合物的合成、结构及催化活性

设计合成了2个结构新颖的半夹心单核聚吡唑硼酸盐羧酸配合物Tp^*Co(Hglu)(CH₃OH)(1)和Tp^*Co(Hsub)(H₂O)(2)[Tp^*=三聚(3,5-二甲基吡唑)硼酸根, H₂glu=戊二酸, H₂sub=辛二酸], 并通过元素分析、 红外光谱、 紫外-可见光谱和X射线单晶结构分析对标题配合物进行了表征. 结构分析表明, 在配合物1和2中, 配体Tp^*都是三齿配位, 配位模式相同; 戊二酸和辛二酸都以μ₁-η¹-η¹的端基配位模式与金属相连. 此外, 还对配合物的热稳定性进行了详细分析, 并初步探讨了配合物催化氧化环己烷的催化活性.     

Synthesis and characterization of uranium(III) compounds supported by the hydrotris(3,5-dimethyl-pyrazolyl)borate ligand: Crystal structures of [U(Tp)2(X)] complexes (X = OC6H2-2,4,6-Me3, dmpz, Cl)

Reaction of [U(Tp^Me2)₂(NR₂)] (R = Ph, SiMe₃) with protic substrates such as 2,4,6-trimethylphenol (HOC₆H₂-2,4,6-Me₃), 3,5-dimethylpyrazole (Hdmpz), 2-mercaptopyridine (HSC₅H₄N) and phenylacetylene (HCCPh) afforded the corresponding [U(Tp^Me2)₂(OAr)] (Ar = C₆H₂-2,4,6-Me₃) (1), [U(Tp^Me2)₂(dmpz)] (2), [U(Tp^Me2)₂(η²-SC₅H₄N)] (3), and [U(Tp^Me2)₂(CCPh)] (4) compounds. Reaction of [U(Tp^Me2)₂(NR₂)] with Me₃SnCl or Me₃SiBr gave [U(Tp^Me2)₂Cl] (5) and [U(Tp^Me2)₂Br] (6), respectively, in high yield. The amido precursors failed to react with cyclopentadiene, but metathesis of [U(Tp^Me2)₂I] with NaCp yielded [U(κ³-Tp^Me2)(κ²-Tp^Me2)(η⁵-Cp)] (7). Thermolysis of 7 resulted in oxidation of the metal centre and redistribution of the ligands, giving [UCp₃(dmpz)] (8), pyrazabole (9) and [U(Tp^Me2)(dmpz)₃] (10). The complexes have been fully characterized by spectroscopic methods and the structures of 1, 2, and 5 were confirmed by X-ray crystallographic studies. In the solid state the complexes exhibit distorted pentagonal bipyramidal geometries.     

Mixed‐Valence Thallium(I,III) Bromides The Crystal Structure of α—Tl2Br3

Thallium sesquibromide Tl₂Br₃ is dimorphic. Scarlet coloured crystals of α‐Tl₂Br₃ were obtained by reactions of aqueous solutions of TlBr₃ and Tl₂SO₄ in agarose gel. In case of rapid crystallisation of hydrous TlBr₃/TlBr solutions and from TlBr/TlBr₂ melts ß‐Tl₂Br₃ is formed as scarlet coloured, extremely thin lamellae. The crystal structures of both forms are very similar and can be described as mixed‐valence thallium(I)‐hexabromothallates(III) Tl₃[TlBr₆]. In the monoclinic unit cell of α‐Tl₃[TlBr₆] (a = 26.763(7) Å; b = 15.311(6) Å; c = 27.375(6) Å; β = 108.63(2)°, Z = 32, space gr. C2/c) the 32 Tl^III‐cations are found in strongly distorted octahedral TlBr₆ groups. The 96 Tl^I cations are surrounded either by four or six TlBr₆ groups with contacts to 8 or 9 Br neighbors. Crystals of β‐Tl₃[TlBr₆] by contrast show almost hexagonal metrics (a = 13.124(4) Å, b = 13.130(4) Å, c = 25.550(7) Å, γ = 119.91(9)°, Z = 12, P2₁/m). Refinements of the parameters revealed structural disorder of TlBr₆ units, possibly resulting from multiple twinning. Both structures are composed of Tl₂[TlBr₆]^— and Tl₄[TlBr₆]⁺ multilayers, which alternate parallel (001). The structural relationships of the complicated structures of α‐ and β‐Tl₃[TlBr₆] to the three polymorphous forms of Tl₂Cl₃ as well as to the structures of monoclinic hexachlorothallates M₃TlCl₆ (M = K, Rb) and the cubic elpasolites are discussed.     

A Missing Structural Link in the Werner Series of Cobalt(III) Complexes: The Crystal Structure of Δ‐(–)589‐Tris(ethylenediamine)cobalt(III) Iodide Monohydrate

Alfred Werner's historic resolution of Δ/Λ‐[Co(en)₃]³⁺ (where en = ethylenediamine) provided conclusive evidence for octahedral geometry coordination compounds and the first example of chirality in an inorganic molecule. Herein, we report the historically significant structure and absolute configuration of Δ‐(–)₅₈₉‐tris(ethylenediamine) cobalt(III) iodide monohydrate, Δ‐[Co(en)₃]I₃ ( 1 ), the missing crystallographic piece in the series of [Co(en)₃]³⁺ complexes. Complex 1 crystallizes in an orthorhombic space group P2₁2₁2₁ with unit cell dimensions of a = 8.4016(10), b = 11.2573(13), c = 18.825(2) Å, V = 1780.4(4) ų, and Z = 4. The absolute configuration of the complex cation [Co(en)₃]³⁺ is Δ and the en ligands adopt a λλδ configuration.     

Synthesis,Characterization and Crystal Structure of Dimeric {[(AMTTO)2Ag]NO3}2 (AMTTO = 4‐Amino‐6‐methyl‐1, 2, 4‐triazine‐3(2H)‐thione‐5‐one)

The reaction of 4‐Amino‐6‐methyl‐1, 2, 4‐triazine‐3(2H)‐thione‐5‐one (AMTTO, 1 ) with silver nitrate in methanol led to the dimeric complex {[(AMTTO)₂Ag]NO₃}₂ ( 2 ). 2 was characterized by elemental analyses and IR spectroscopy as well as by X‐ray structure analysis. Crystal data for 2 at ?80 °C: crystal system orthorhombic, space group P2₁2₁2₁ with a = 1043.6(1), b = 1329.6(1), c = 2358.4(1) pm, Z = 8 and R₁ = 0.037. The cation possesses a highly distorted linear coordination sphere in the solid state.