β‐Rubidium antimonide,Rb4Sb4

β‐RbSb crystallizes with the LiAs structure type. As in the α phase (NaP type), Sb^? forms approximate 4₁ helical chains (2₁ crystallographic symmetry), with Sb—Sb distances of 2.838 (1) and 2.862 (1) Å. In contrast to the α phase, the helices have different chirality.     

Influence of the Counterions on the Structures of Ternary Zn/Sn/Se Anions: Synthesis and Properties of [Rb10(H2O)14.5][Zn4(μ4‐Se)2(SnSe4)4] and [Ba5(H2O)32][Zn5Sn(μ3‐Se)4(SnSe4)4]

Reactions of rubidium or barium salts of the ortho‐selenostannate anion, [Rb₄(H₂O)₄][SnSe₄] ( 1 ) or [Ba₂(H₂O)₅][SnSe₄] ( 2 ) with Zn(OAc)₂ or ZnCl₂ in aqueous solution yielded two novel compounds with different ternary Zn/Sn/Se anions, [Rb₁₀(H₂O)_14.5][Zn₄(μ₄‐Se)₂(SnSe₄)₄] ( 3 ) and [Ba₅(H₂O)₃₂][Zn₅Sn(μ₃‐Se)₄(SnSe₄)₄] ( 4 ). 1 – 4 have been determined by means of single crystal X‐ray diffraction: 1 : triclinic space group lattice dimensions at 203 K: a = 8.2582(17) Å, b = 10.634(2) Å, c = 10.922(2) Å, α = 110.16(3)°, β = 91.74(3)°, γ = 97.86(3)°, V = 888.8(3) ų; R₁ [I > 2σ(I)] = 0.0669; wR₂ = 0.1619; 2 : orthorhombic space group Pnma; lattice dimensions at 203 K: a = 17.828(4) Å, b = 11.101(2) Å, c = 6.7784(14) Å, V = 1341.5(5) ų; R₁ [I > 2σ(I)] = 0.0561; wR₂ = 0.1523; 3 : triclinic space group ; lattice dimension at 203 K: a = 17.431(4) Å, b = 17.459(4) Å, c = 22.730(5) Å, α = 105.82(3)°, β = 99.17(3)°, γ = 90.06(3)°, V = 6563.1(2) ų; R₁ [I > 2σ(I)] = 0.0822; wR₂ = 0.1782; 4 : monoclinic space group P2₁/c; lattice dimensions at 203 K: a = 25.231(5) Å, b = 24.776(5) Å, c = 25.396(5) Å, β = 106.59(3)°, V = 15215.0(5) ų; R₁ [I > 2σ(I)] = 0.0767; wR₂ = 0.1734. The results serve to underline the crucial role of the counterion for the type of ternary anion to be observed in the crystal. Whereas Rb⁺(aq) stabilizes a P1‐type Zn/Sn/Se supertetrahedron in 3 like K⁺, the Ba²⁺(aq) ions better fit to an anionic T3‐type Zn/Sn/Se cluster arrangement as do Na⁺ ions. It is possible to estimate a radius:charge ratio for the stabilization of the two structural motifs.     

Alkalimetall‐Oxoantimonate: Synthesen,Kristallstrukturen und Schwingungsspektren von ASbO2 (A = K,Rb), A4Sb2O5 (A = K,Rb, Cs) und Cs3SbO4

Alkaline Metal Oxoantimonates: Synthesis, Crystal Structures, and Vibrational Spectroscopy of ASbO₂ (A = K, Rb), A₄Sb₂O₅ (A = K, Rb, Cs), and Cs₃SbO₄ The compounds ASbO₂ (A = K/Rb; monoclinic, C2/c, a = 785.4(3)/799.6(1) pm, b = 822.1(4)/886.32(7) pm, c = 558.7(3)/559.32(5) pm, β = 124.9(1)/123.37(6)°, Z = 4) are isotypic with CsSbO₂ and the corresponding bismutates. The structures of the antimonates A₄Sb₂O₅ (A = K/Rb: orthorhombic, Cmcm, a = 394.9(1)/407.34(7) pm, b = 1807.4(1)/1893.5(1) pm, c = 636.34(9)/655.60(8) pm, Z = 2) and Cs₄Sb₂O₅ (monoclinic, Cm, a = 1059.81(7) pm, b = 692.68(8) pm, c = 811.5(1) pm, β = 98.7(1)°, Z = 2) both contain the anion [O₂SbOSbO₂]^4–. Cs₃SbO₄ (orthorhombic, Pnma, a = 1296.1(1) pm, b = 919.24(8) pm, c = 679.95(6) pm, Z = 4) crystallizes with the K₃NO₄ structure type.     

Cd13−xInySb10 (x≈2.7, y≈1.5): An Interstitial‐Free Variant of Thermoelectric β‐Zn4Sb3

Although free from structural disorder , the new intermetallic compound Cd_13?xIn_ySb₁₀ (see figure) displays similarly low thermal conductivity values as disordered thermoelectric β‐Zn₄Sb₃ with an isostructural framework.

     

Bis(5‐hydroxy‐2‐hydroxy­methyl‐4‐pyrone‐κ2O4,O5)bis(2‐hydroxy­methyl‐5‐oxido‐4‐pyrone‐κ2O4,O5)­calcium(II) tetrahydrate

In the title compound, [Ca(C₆H₅O₄)₂(C₆H₆O₄)₂]·4H₂O, which is a kojic acid–Ca²⁺ complex, the Ca atom is on a twofold axis and is octacoordinated by O atoms from four pyrone ligand mol­ecules. The hydroxyl and ketone O atoms of each ligand form a five‐membered chelate ring with the Ca atom. The crystal structure is stabilized by partial stacking and O—H?O hydrogen bonds.     

Energetic Derivatives of 4, 4′,5, 5′‐Tetranitro‐2, 2′‐bisimidazole (TNBI)

4, 4′,5, 5′‐Tetranitro‐2, 2′‐bisimidazole (TNBI) was synthesized by nitration of bisimidazole (BI) and recrystallized from acetone to form a crystalline acetone adduct. Its ammonium salt ( 1 ) was obtained by the reaction with gaseous ammonia. In order to explore new explosives or propellants several energetic nitrogen‐rich 2:1 salts such as the hydroxylammonium ( 3 ), guanidinium ( 4 ), aminoguanidinium ( 5 ), diaminoguanidinium ( 6 ) and triaminoguanidinium 7 4, 4′,5, 5′‐tetranitro‐2, 2′‐bisimidazolate were prepared by facile metathesis reactions. In addition, methylated 1, 1′‐dimethyl‐4, 4′,5, 5′‐tetranitro‐2, 2′‐bisimidazole (Me₂TNBI, 8 ) was synthesized by the reaction of 2 and dimethyl sulfate. Metal salts of TNBI can also be easily synthesized by using the corresponding metal bases. This was proven by the synthesis of pyrotechnically relevant dipotassium 4, 4′,5, 5′‐tetranitro‐2, 2′‐bisimidazolate ( 2 ), which is a brilliant burning component e.g. in near‐infrared flares. All compounds were characterized by single crystal X‐ray diffraction, NMR and vibrational spectroscopy, elemental analysis and DSC. The sensitivities were determined by BAM methods (drophammer and friction tester). The heats of formation were calculated using CBS‐4M electronic enthalpies and the atomization method. With these values and mostly the X‐ray densities different detonation parameters were computed by the EXPLO5 computer code. Due to the great thermal stability and calculated energetic properties, especially guanidinium salt 4 could be served as a HNS replacement.     

Diastereoselective synthesis of (2R,4S,5S)‐(+)‐5‐(2,2‐dichloroacetamido)‐ 4‐(4‐nitrophenyl)‐2‐aryl‐1,3‐dioxanes

(2R,4S,5S)‐(+)‐5‐(2,2‐Dichloroacetamido)‐4‐(4‐nitrophenyl)‐2‐aryl‐1,3‐dioxanes 3–8 were synthesized with high diastereoselectivity and good yields. The structures of acetals were determined and the configurations were confirmed by 2D‐NMR (NOESY) and X‐ray crystallographic analysis.     

Synthese und Strukturen von [Cu8As3(AsSiMe3)2(dppb)4]+‐[Cu{As2(SiMe3)2}{As4(SiMe3)4}]‐, [Cu8As3(AsSiMe3)2(dppb)4]+‐[Cu{As(SiMe3)2}2]‐ und [Cu10(Sb3)2(SbSiMe3)2(dppm)6]

The reaction of CuCl, LiAs(SiMe₃)₂ and dppb (Bis(diphenylphosphino)butane) leads to the formation of ionic cluster complexes. Depending on the reaction conditions one can isolate [Cu₈As₃(AsSiMe₃)₂(dppb)₄]⁺[Cu{As₂(SiMe₃)₂}{As₄(SiMe₃)₄}]^‐ ( 1 ) and [Cu₈As₃(AsSiMe₃)₂(dppb)₄]⁺[Cu{As(SiMe₃)₂}₂]^‐ ( 2 ). The same reaction of CuCl, dppm (Bis(diphenylphosphino)methane) and LiSb(SiMe₃)₂ leads to the neutral cluster complex [Cu₁₀(Sb₃)₂(SbSiMe₃)₂(dppm)₆] ( 3 ). The structures of 1‐3 have been solved by X‐ray single crystal analyses.     

Bismuth Polyanions in Solution: Synthesis and Structural Characterization of (2, 2, 2‐crypt‐A)2Bi4 (A = K,Rb) and the Formation of the Laves Phases ABi2 (A = K,Rb, Cs) from Solution

The possibility to synthesize and isolate different types of bismuth polyanions by dissolving various intermetallic precursors (binary samples from A‐Bi or ternary samples from A‐A'‐Bi systems, A and A' = K, Rb, Cs) in ethylenediamine or dimethylform amide in the presence of sequestering agents (2, 2, 2‐crypt or 18‐crown‐6) was investigated. The crystals of (2, 2, 2‐crypt‐K)₂Bi₄ ( 1 ) and (2, 2, 2‐crypt‐Rb)₂Bi₄ ( 2 ) compound were obtained from such solutions, the latter for the first time, and their structures were determined. The two compounds are isostructural (P1, Z=1, a = 11.052(2) Å, b = 11.370(2) Å, c = 11.698(2) Å, α = 61.85(3) °, β = 82.58(3) °, γ = 81.87(3) °, R₁ = 0.058, wR² = 0.149 for 1 and a = 11.181(2) Å, b = 11.603(2) Å, c = 11.740(2) Å, α = 61.96(3) °, β = 81.45(3) °, γ = 82.26(3) °, R₁ = 0.041, wR² = 0.109) and contain Bi₄^2— square planar cluster anions and cryptated alkali metal cations. In the case of the presence of 18‐crown‐6 the Laves phases ABi₂ (A = K, Rb, Cs) could be isolated from the solutions. A mechanism for the formation of ABi₂ is proposed.     

(5Z)‐4‐Amino‐2‐(4‐hydroxyphenyl)‐1H‐imidazol‐5(2H)‐one oxime 3‐oxide

The title molecule, C₉H₁₀N₄O₃, consists of benzene and imidazole rings which are almost perpendicular to each other. A hydroxyimino group is directly linked to the imidazole ring with a double C=N bond, which is the first example in this type of compound. The double bond may be a good location for the initiation of various reactions with a wide range of potential applications. In the crystal structure, there are π–π interactions between molecules related by a centre of symmetry, with the imidazole and benzene rings almost completely overlapped. The molecules are hydrogen bonded in each direction and form a three‐dimensional hydrogen‐bond network.     

Zinc(II) and Cadmium(II) Complexes of the 3‐(2‐Pyridyl)‐5,6‐diphenyl‐1,2,4‐triazine (PDPT) Ligand,Structural Studies of [Zn(PDPT)2Cl(ClO4)] and [Cd(PDPT)2(NO3)(ClO4)]

Two new mixed‐anion zinc(II) and cadmium(II) complexes of 3‐(2‐pyridyl)‐5,6‐diphenyl‐1,2,4‐triazine (PDPT) ligand, [Zn(PDPT)₂Cl(ClO₄)] and [Cd(PDPT)₂(NO₃)(ClO₄)], have been synthesized and characterized by elemental analysis, IR‐ and ¹H NMR spectroscopy. The single crystal X‐ray analyses show that the coordination number in these complexes is six with four N‐donor atoms from two “PDPT” ligand and two of the anionic ligands, ZnN₄ClO_perchlorate, CdN₄O_nitrateO_perchlorate. Self‐assembly of these compounds in the solid state via π–π‐stacking interactions is discussed.     

[Zn2(thf)2(EtZn)6Zn4(μ4‐O)(tBuPO3)8]: A Dodecanuclear Zincophosphonate Aggregate with a Zn4(μ4‐O) Core

The largest multinuclear zinc framework synthesized is in the title compound (see picture), which contains structural features closely related to the motifs found in layered and three‐dimensional zincophosphates and zincophosphonates. The reactive centers make this zincophosphonate a viable precursor for the synthesis of porous zincophosphonate materials.     

Rhodium(I) and Silver(I) Complexes of 4, 5‐Dicyano‐1, 3‐dimesityl‐ and 4, 5‐Dicyano‐1, 3‐dineopentylimidazol‐2‐ylidene

The new N‐heterocyclic carbene (NHC) precursors 4, ‐dicyano‐1, ‐dimesityl‐ ( 9 ) and 4, 5‐dicyano‐1, 3‐dineopentyl‐2‐(pentafluorophenyl)imidazoline ( 14 ) were synthesized. The structure of 9 could be determined by X‐ray crystallography. With the 2‐pentafluorophenyl‐substituted imidazolines 9 and 14 , the [AgCl(NHC)], [RhCl(COD)(NHC)], and [RhCl(CO)₂(NHC)] complexes [NHC = 4, 5‐dicyano‐1, 3‐dimesitylimidazol‐2‐ylidene ( 3 ) and 4, 5‐dicyano‐1, 3‐dineopentylimidazol‐2‐ylidene ( 4 )] were obtained. Crystal structures of [AgCl( 3 )] ( 15 ), [RhCl(COD)( 3 )] ( 17 ), [RhCl(COD)( 4 )] ( 18 ), and [RhCl(CO)₂( 3 )] ( 19 ) were solved and with the crystal data of 19 , the percent buried volume ( %V_bur) of 31.8(±0.1) % was determined for NHC 3 . Infrared spectra of the imidazolines 9 and 14 and of the complexes 15 – 20 were recorded and the CO stretching frequencies of complexes 19 and 20 were used to determine the Tolman electronic parameters of the newly obtained NHCs 3 (TEP: 2060 cm^–1) and 4 (TEP: 2061 cm^–1), thus proving that 1, 3‐substitution of maleonitrile‐NHCs does not have a significant effect for the high π‐acceptor strength of these carbenes.     

Two tetranuclear zinc clusters, [Zn4(μ3‐OEt)2(μ2‐MalO)4Et2] and [Zn4(μ3‐GueO)2(μ2‐GueO)2(μ2‐MalO)2(MalO)2]·2C7H8, containing defective dicubane core geometries (MalOH is maltol and GueOH is guethol)

The zinc alkoxide molecules in di‐μ₃‐ethanolato‐diethyltetrakis(μ₂‐2‐methyl‐4‐oxo‐4H‐pyran‐3‐olato‐κ³O³,O⁴:O³)tetrazinc(II), [Zn₄(C₂H₅)₂(C₂H₅O)₂(C₆H₅O₃)₄], (I), and bis(μ₃‐2‐ethoxyphenolato‐κ⁴O¹,O²:O¹:O¹)bis(μ₂‐2‐ethoxyphenolato‐κ³O¹,O²:O¹)bis(μ₂‐2‐methyl‐4‐oxo‐4H‐pyran‐3‐olato‐κ³O³,O⁴:O³)bis(2‐methyl‐4‐oxo‐4H‐pyran‐3‐olato‐κ²O³,O⁴)tetrazinc(II) toluene disolvate, [Zn₄(C₆H₅O₃)₄(C₈H₉O₂)₄]·2C₇H₈, (II), lie on crystallographic centres of inversion. The asymmetric units of (I) and (II) contain half of the tetrameric unit and additionally one molecule of toluene for (II). The Zn^II atoms are four‐ and six‐coordinated in distorted tetrahedral and octahedral geometries for (I), and six‐coordinated in a distorted octahedral environment for (II). The Zn^II atoms in both compounds are arranged in a defect dicubane Zn₄O₆ core structure composed of two EtZnO₃ tetrahedra and ZnO₆ octahedra for (I), and of four ZnO₆ octahedra for (II), sharing common corners. The maltolate ligands exist mostly in a μ₂‐bridging mode, while the guetholate ligands prefer a higher coordination mode and act as μ₃‐ and μ₂‐bridges.     

Routhierite,Tl(Cu,Ag)(Hg,Zn)2(As,Sb)2S6

The crystal structure of the mineral routhierite, Tl(Cu,Ag)(Hg,Zn)₂(As,Sb)₂S₆, was solved and refined for the first time by means of single‐crystal X‐ray diffraction. The crystal structure consists of (Cu,Ag)S₄ and (Hg,Zn)S₄ tetrahedra, which share corners to form a framework with channels parallel to [001]. These channels contain TlS₆ and (As,Sb)S₃ polyhedra that share corners and edges with the tetrahedra. The crystal–chemical relationships with other Tl–Hg sulfosalts are outlined. The structure determination reported in this study definitively confirms that routhierite and stalderite possess the same crystal structure.     

[μ‐(Me3SiCH2Sb)5–Sb1,Sb3–{W(CO)5}2] und [{(Me3Si)2CHSb}3Fe(CO)4] – zwei cyclische Komplexe mit Antimon‐Liganden

Syntheses and Crystal Structures of [μ‐(Me₃SiCH₂Sb)₅–Sb¹,Sb³–{W(CO)₅}₂] and [{(Me₃Si)₂CHSb}₃Fe(CO)₄] – Two Cyclic Complexes with Antimony Ligands cyclo‐(Me₃SiCH₂Sb)₅ reacts with [(THF)W(CO)₅] (THF = tetrahydrofuran) to form cyclo‐[μ‐(Me₃SiCH₂Sb)₅–Sb¹,Sb³–{W(CO)₅}₂] ( 1 ). The heterocycle cyclo‐ [{(Me₃Si)₂CHSb}₃Fe(CO)₄] ( 2 ) is formed by an insertion reaction of cyclo‐[(Me₃Si)₂CHSb]₃ and [Fe₂(CO)₉]. The crystal structures of 1 and 2 are reported.