Structural Characterization and Thermal Behavior of 1-Amino-1-methylamino-2,2-dinitroethylene

A novel high energetic material, 1‐amino‐1‐methylamino‐2,2‐dinitroethylene (AMFOX‐7), was synthesized through 1,1‐diamino‐2,2‐dinitroethylene (FOX‐7) reacting with methylamine in N‐methyl pyrrolidone (NMP) at 80.0°C, and its structure was determined by single crystal X‐ray diffraction. The crystal is monoclinic, space group P2₁/m with crystal parameters of a=6.361(3) Å, b=7.462(4) Å, c=6.788(3) Å, β=107.367(9)°, V=307.5(3) ų, Z=2, µ=0.160 mm^?1, F(000)=168, D_c=1.751 g·cm^?3, R₁=0.0463 and wR₂=0.1102. Thermal decomposition of AMFOX‐7 was studied, and the enthalpy, apparent activation energy and pre‐exponential constant of the exothermic decomposition reaction are 303.0 kJ·mol^?1, 230.7 kJ·mol^?1 and 10^21.03 s^?1, respectively. The critical temperature of thermal explosion is 245.3°C. AMFOX‐7 has higher thermal stability than FOX‐7.     

Syntheses and Crystal Structures of Copper(II) and Copper(I) dpp Complexes, [Cu(dpp)Br2] and [Cu(dpp)2][CuBr2] (dpp = 2,9‐diphenyl‐1,10‐phenanthroline)

The complexes [Cu(dpp)Br₂] ( 1 ) and [Cu(dpp)₂][CuBr₂] ( 2 ) (dpp = 2,9‐diphenyl‐1,10‐phenanthroline) were synthesized and characterized by single‐crystal X‐ray diffraction methods. Reaction of copper(II) bromide with the dpp ligand in dichloromethane at room temperature afforded 1 , which is a rare example of non‐square planar four‐coordinate copper(II) complexes. Complex 1 crystallizes in the monoclinic space group C2/c with a = 15.352(3), b = 13.192(3), c = 11.358(2) Å, β = 120.61(3)°, V = 1979.6(7) ų, Z = 4, D_calc = 1.865 g cm^?3. The coordination geometry about the copper center is distorted about halfway between square planar and tetrahedral. The Cu‐N distance is 2.032(2) Å and the Cu‐Br distance 2.3521(5) Å. Heating a CH₂Cl₂ or acetone solution of 1 resulted in complex 2 , which consists of a slightly distorted tetrahedral [Cu(dpp)₂]⁺ cation and a linear two‐coordinate [CuBr₂]^? anion. 2 crystallizes in the triclinic space group with a = 10.445(2), b = 11.009(2), c = 18.458(4) Å, α = 104.72(3), β = 94.71(3), γ = 103.50(3)°, V = 1973.3(7) ų, Z = 2, D_calc = 1.602 g cm^?3. The four Cu(1)‐N distances are between 2.042(3) and 2.067(3) Å, the distance of Cu(2)‐Br(1) 2.2268(8) Å, and the disordered Cu(3)‐Br(2) distances are 2.139(7) and 2.237(4) Å, respectively. Complex 2 could also be prepared by directly reacting CuBr with dpp in CH₂Cl₂.     

一种新型螺旋桨状配体构型的锰（N-苯甲醛-N’-水杨酰腙）配合物的合成、晶体结构和生物活性研究

本文合成并表征了一种新型螺旋桨状配体构型的锰配合物,其结构式为[Mn(N’-benzylidenesalicylhydrazide)3(H2O)]。该配合物的晶体结构用X-射线单晶衍射测定。配合物的晶体为三斜晶系,空间群P-1,晶胞参数：a=11.6411Å,b=12.728Å,c=16.346Å,α=110.357°,β=96.555°,γ=108.996°,V=2075.2Å3,Z=2,Dcalc=1.265g/cm3。在该配合物中,金属离子为八面体配位形式,使得三个配体以一种螺旋桨状的立体结构排列在它周围。抗菌活性试验表明,对受试微生物,配合物比配体表现出更强烈的活性。     

Palladium(II) Complexes with the Mixed‐Donor Ligand CH3S‐(CH2)3‐PPh2 Crystal Structures of [PdCl2{CH3S‐(CH2)3‐PPh2}n](n = 1, 2)

The phosphorus‐sulfur ligand 1‐(methylthio)‐3‐(diphenylphosphino)‐propane (S‐P3) has been synthesized and characterized by ¹H NMR and ¹³C NMR. Reactions of S‐P3 with [PdCl₂(PhCN)₂] afforded the complexes [PdCl₂(S‐P3)] ( I ) and [PdCl₂(S‐P3)₂] ( II ), in which S‐P3 acts as a bidentate and monodentate ligand, respectively. Compound I crystallizes in monoclinic space group P2₁/n (No. 14) with cell dimensions: a = 8.589(3), b = 15.051(3), c = 17.100(3)Å, β = 102.91(2)°, V = 2154.7(9)ų, Z = 4. Likewise, compound II crystallizes in monoclinic space group P2₁/n (No. 14) with a = 9.993(5), b = 8.613(4), c = 18.721(5)Å, β = 90.18(3)°, V = 1611.3(12)ų, Z = 2. Compound II has a trans square planar configuration with only the P‐site of the ligand bonded to the palladium atom.     

Synthesis of an axially chiral Ir–NHC complex derived from BINAM

The Ir–NHC complex 6 was successfully synthesized from the reaction of axially chiral binaphthyl dibenzimidazolium salt 5 with [Ir(COD)Cl]₂ (COD = 1,5‐cyclooctadiene) in tetrahydrofuran in the presence of KO^tBu base under reflux. Its unique crystal structure is unambiguously disclosed by X‐ray diffraction. Complex 6 is orthorhombic, with space group P2₁2₁2₁, unit cell dimensions a = 12.1406(16) Å, b = 19.110(3) Å, c = 20.312(3) Å, α = β = γ = 90° and volume 4712.6(11) ų, Z = 4, D_calc = 1.930 Mg m^?3. Copyright © 2004 John Wiley & Sons, Ltd.     

Synthesis,Crystal Structure and Thermal Behavior of 4,5‐Diacetoxyl‐2‐(dinitromethylene)‐imidazolidine

A new energetic material, 4,5‐diacetoxyl‐2‐(dinitromethylene)‐imidazolidine (DADNI), was synthesized by the reaction of 4,5‐dihydroxyl‐2‐(dinitromethylene)‐imidazolidine (DDNI) and acetic anhydride, and characterized by single crystal X‐ray diffraction. Crystal data for DADNI are monoclinic, space group C2/c, a=15.9167(3) Å, b=8.6816(4) Å, c=8.5209(3) Å, β=103.294(9)°, V=1145.9(3) ų, Z=4, µ=0.150 mm⁻¹, F(000)=600, D_c=1.682 g·cm⁻³, R₁=0.0565 and wR₂=0.1649. Thermal decomposition behavior of DADNI was studied and an intensely exothermic process was observed. The kinetic equation of the decomposition reaction is: dα/dT=(10^16.64/β)×4α^3/4exp(−1.582×10⁵/RT). The critical temperature of thermal explosion is 163.76°C. The specific heat capacity of DADNI was studied with micro‐DSC method and theoretical calculation method. The molar heat capacity is 343.30 J·mol⁻¹·K⁻¹ at 298.15 K. The adiabatic time‐to‐explosion of DADNI was calculated to be 87.7 s.     

m -Terphenyl derivative of titanium(III): Cp2TiR (Cp=C5H5; R =2,6-(4-MeC6H4)2C6H3)

The title compound, Cp₂TiR (Cp=C₅H₅; R=2,6-(4-MeC₆H₄)₂C₆H₃), 1, was prepared by reaction of RLi with [Cp₂TiCl]₂. Compound 1 was characterized by elemental analysis, EPR, and single crystal X-ray crystallography. The title compound crystallizes in the monoclinic space group C2/c with the following unit cell dimensions: a=11.1466(7) Å, b=16.4429(11) Å, c=13.0786(8) Å; b=106.2040(10)^°;V=2301.9(3) ų. The EPR spectrum of 1 displays two signals, a high field signal at g=1.979 and a lower field signal at g=1.959. Significantly, 1 is a sterically encumbered m-terphenyl-stabilized trivalent titanocene paramagnetic complex and may be a practical one-electron reducing reagent.     

Hydrothermal Synthesis and Structures of Two New Molybdenum Phosphate Compounds based on Keggin Cluster Units

Two new molybdenum phosphate complexes, [Cu₂(phen)₄(μ‐Cl)][PMo₁₂O₄₀]·H₂O (phen = 1,10‐phenanthroline) ( 1 ) and (Hbpy)[Cu^I(bpy)]₂[PMo^V₂Mo^VI₁₀O₃₉] (bpy = 4,4′‐bipyridine) ( 2 ), have been prepared under mild hydrothermal conditions and structurally characterized by single‐crystal X‐ray diffraction. Compounds 1 and 2 crystallize in triclinic system, space group , with a = 12.5458(7) Å, b = 13.4486(8) Å, c = 21.2406(12) Å, α = 99.7020(10)°, β = 94.2320(10)°, γ = 95.0890(10)°, V = 3504.2(3) ų and Z = 2 for 1 , and a = 10.7871(6) Å, b = 10.9016(6) Å, c = 12.7897(7) Å, α = 96.8500(10)°, β = 110.0850(10)°, γ = 103.5800(10)°, V = 1339.74(13) ų and Z = 1 for 2 . Compound 1 contains a [Cu₂(phen)₄(μ‐Cl)]³⁺ cation in which two similar [Cu(phen)₂] units are bridged by one chlorine atom. Compound 2 contains one‐dimensional straight chain of Keggin polyoxoanions [PMo^V₂Mo^VI₁₀O₃₉]_n^3? and two linear cationic chains of [Cu^I(bpy)]_nⁿ⁺. The molecular packing shows a two‐dimensional network, which is formed by the cross of the linear Keggin anions and Cu‐bpy cations.     

Ionothermal Synthesis and Structural Characterization of a Novel Open Framework Zinc Diphosphonate with Carboxylate‐like Linker

A novel crystalline zinc diphosphonate, (CH₃NH₃ )₄Zn₂ (xbp)₂•H₂O , denoted as compound 1 , was ionothermally synthesized from tetraethyl‐p ‐xylylenebisphosphonate (Texbp) and Zn(OAc )₂ in a protic eutectic mixture with urea/methylamine hydrochloride. Its structure was determined by single‐crystal X‐ray diffraction data and had a special three‐dimensional open framework with rhombic channels. Compound 1 belongs to the monoclinic system (space group C2 /c ), with lattice parameters a =22.6876(19) Å, b =8.73 76(7) Å, c =8.1673(9) Å, β =108.146(2)°, V =1538.5(2) ų, Z =2. Its structure is totally different from the typical organic pillared structure, only two oxygens of the phosphonate group are coordinated with zinc atoms, and the third oxygen exists in the terminal form, which is similar to the popular dicarboxylate linkers in MOFs . The organic cations [CH₃NH₃ ]⁺ of the eutectic mixture played a structure‐directing role for constructing this framework and were confined in the pore channels to balance the negative charges resulting from the zinc phosphonate inorganic chains.     

Synthesis and Crystal Structures of the First Quaternary Tantalum Thiogermanates,ATaGeS5 (A = K,Rb, Cs)

The new quaternary thiogermanates, ATaGeS₅ (A = K, Rb, Cs) were prepared with the use of halide fluxes and the crystal structures of the compounds were determined by single‐crystal X‐ray diffraction methods. The compounds are isostructural and crystallize in space group P\bar{1} of the triclinic system with two formula units in a cell of dimensions: a = 6.937(1) Å, b = 6.950(2) Å, c = 8.844(3) Å, α = 71.07(2)°, β = 78.56(2)°, γ = 75.75(2)°, V = 387.6(2) Å³ for KTaGeS₅; a = 6.996(3) Å, b = 7.033(3) Å, c = 8.985(4) Å, α = 70.33(3)°, β = 78.12(4)°, γ = 75.63(4)°, V = 399.6(3) Å³ for RbTaGeS₅; a = 7.012(4) Å, b = 7.202(3) Å, c = 9.267(5) Å, α = 68.55(3)°, β = 77.27(4)°, γ = 74.75(4)°, V = 416.2(4) Å³ for CsTaGeS₅. The structures of ATaGeS₅ (A = K, Rb, Cs) are comprised of anionic infinite two‐dimensional {}_\infty^2 [TaGeS₅^–] layers separated from one another by alkali metal cations (A⁺). Each layer is made up of tantalum centered sulfur octahedra and pairs of edge‐sharing germanium centered sulfur tetrahedra. The classical charge valence of these compounds should be represented by [A⁺][(Ta⁵⁺)(Ge⁴⁺)(S^2–)₅]. UV/Vis diffuse reflectance measurements indicate that they are semiconductors with optical bandgaps of ca. 2.0 eV.     

Synthesis,Characterization, and Crystal Structures of [Cu(ca2en)2]ClO4, and [Cu(ca2en)(PPh3)2]ClO4 Complexes

Synthesis, spectroscopy, and crystal structures of [Cu(ca₂en)₂]ClO₄ ( 1 ) and [Cu(ca₂en)(PPh₃)₂]ClO₄ ( 2 ) (ca₂en=N,N′‐bis(trans‐cinnamaldehyde)ethylenediimine) are reported. Compound 1 crystallizes in the orthorhombic space group Pbca, with a=12.5647(7), b=21.8203(11), c=27.992(2) Å, V=7674.3(7) ų, Z=8. Compound 2 crystallizes in the triclinic space group P , with a=13.0540(11), b=14.2935(13), c=14.9863(13) Å, α=84.130(2), β=69.761(2), γ=87.749(2)°, V=2609.8(4) ų, Z=2. The coordination polyhedron about the Cu^I center in the two complexes is best described as a distorted tetrahedron. The ¹H‐NMR and electronic spectra of these complexes are also reported and discussed. The cyclic voltammetry of the complexes indicate a quasireversible redox behavior for complex 1 (E_1/2=0.51 V). However, complex 2 displays an irreversible oxidation wave at 0.91 V. A weak emission is observed for complex 2 in CHCl₃ at room temperature.     

Synthesis and X-ray investigation of Rb<Subscript>2</Subscript>[Pd(NO<Subscript>3</Subscript>)<Subscript>4</Subscript>] and Cs<Subscript>2</Subscript>[Pd(NO<Subscript>3</Subscript>)<Subscript>4</Subscript>]

Powder and single crystal X-ray diffraction studies have been performed for anhydrous nitrate complexes Rb₂[Pd(NO₃)₄] (I) and Cs₂[Pd(NO₃)₄] (II). Crystal data for I: a = 7.843(1) Å, b = 7.970(1) Å, c = 9.725(1) Å; β = 100.39(1)°, V = 597.9(1) Å ³, space group P2₁/c, Z = 2, d _calc = 2.918 g/cm³; for II: a = 10.309(2) Å, b = 10.426(2) Å, c = 11.839(2) Å; β = 108.17(3)°, V = 1209.0(4) ų, space group P2₁/c, Z = 4, d ^calc = 3.408 g/cm³. The structures are formed by isolated [Pd(NO₃)₄]^2? complex anions and alkali metal cations. The plane-square environment of the Pd atom is formed from the oxygen atoms of the monodentate nitrate groups. The geometrical characteristics of the complex anions are analyzed. Compound II has a short contact Pd...Cs 3.252 Å.     

Hydrothermal Synthesis,Structure, and Optical Properties of Two Nanosized Ln26@CO3 (Ln=Dy and Tb) Cluster‐Based Lanthanide–Transition‐Metal–Organic Frameworks (Ln MOFs)

Two Ln₂₆@CO₃ (Ln=Dy and Tb) cluster‐based lanthanide–transition‐metal–organic frameworks (Ln MOFs) formulated as [Dy₂₆Cu₃(Nic)₂₄(CH₃COO)₈(CO₃)₁₁(OH)₂₆(H₂O)₁₄]Cl ? 3 H₂O ( 1 ; HNic=nicotinic acid) and [Tb₂₆NaAg₃(Nic)₂₇(CH₃COO)₆(CO₃)₁₁(OH)₂₆Cl(H₂O)₁₅] ? 7.5 H₂O ( 2 ) have been successfully synthesized by hydrothermal methods and characterized by IR, thermogravimetric analysis (TGA), elemental analysis, and single X‐ray diffraction. Compound 1 crystallizes in the monoclinic space group Cc with a=35.775(12) Å, b=33.346(11) Å, c=24.424(8) Å, β=93.993(5)°, V=29065(16) ų, whereas 2 crystallizes in the triclinic space group P with a=20.4929(19) Å, b=24.671(2) Å, c=29.727(3) Å, α=81.9990(10)°, β=88.0830(10)°, γ=89.9940(10)°, V=14875(2) ų. Structural analysis indicates the framework of 1 is a 3D perovskite‐like structure constructed out of CO₃@Dy₂₆ building units and Cu⁺ centers by means of nicotinic acid ligand bridging. In 2 , however, nanosized CO₃@Tb₂₆ units and [Ag₃Cl]²⁺ centers are connected by Nic^? bridges to give rise to a 2D structure. It is worth mentioning that this kind of 4d–4f cluster‐based MOF is quite rare as most of the reported analogous compounds are 3d–4f ones. Additionally, the solid‐state emission spectra of pure compound 2 at room temperature suggest an efficient energy transfer from the ligand Nic^? to Tb³⁺ ions, which we called the “antenna effect”. Compound 2 shows a good two‐photon absorption (TPA) with a TPA coefficient of 0.06947 cm GM^?1 (1 GM=10^?50 cm⁴ s photon^?1), which indicates that compound 2 might be a good choice for third‐order nonlinear optical materials.     

The Structure of Hydrotris(imidazolyl)boratothallium(I) – the First Structurally Authenticated Tris(imidazolyl)borate Metal Complex

The title compound crystallizes in the monoclinic space group P2₁/n with a = 8.706(1), b = 9.192(1), c = 15.261(2) Å, β = 94.740(3)°, V = 1217.0(3) ų, Z = 4, D_calc = 2.278 g cm^–3. The tris(imidazolyl)borate ligand bridges between three thallium atoms. The structure consists of one‐dimensional twisted ladder‐like strands.     

Hydrothermal Preparation,Crystal Structure and Properties of {[ZnTCPP(EtOH)][Zn(en)]2}n(EtOH)2n with a Novel Two‐Dimensional (2‐D) Motif

A novel zinc porphyrin, {[ZnTCPP(EtOH)][Zn(en)]₂}_n(EtOH)_2n ( 1 ) (TCPP=meso‐tetra(4‐carboxyphenyl)‐porphyrin; EtOH=ethanol; en=ethylenediamine) was obtained via a hydrothermal reaction and characterized by single‐crystal X‐ray diffraction. Complex 1 crystallizes in the space group C2/c of the monoclinic system with eight formula units in a cell: a=32.465(4) Å, b=10.527(3) Å, c=31.845(3) Å, β=95.524(6) °, V=10832(4) ų, C₅₈H₅₇N₈O₁₁Zn₃, M_r=1238.23, D_c=1.518 g/cm³, S=1.005, µ(Mo Kα) =1.388 mm^?1, F(000) =5112, R=0.0650 and wR=0.1574. Complex 1 features a novel 2‐D layered motif. The spectral data of UV‐vis, FT‐IR and fluorescence are reported.     

Synthesis of spiro[(6-phenyl-3,4-dihydro-2H-1,3-dioxine)-2<Emphasis Type="Italic">R</Emphasis>(<Emphasis Type="Italic">S</Emphasis>), 3′-(19′,28′-oxidooleanan)]-4-ones and X-ray diffraction analysis of their configuration

The structure of two stereoisomeric spiroadducts of allobetulone with 5-phenyl-2,3-dihydrofuran-2,3-dione was established by X-ray diffraction (XRD) analysis. The crystals of the 2R isomer are orthorhombic, P2₁2₁2₁, a = 10.825(5) Å, b = 12.849(6) Å, c = 23.358(9) Å; V = 3249(2) ų, Z = 4, d _calc = 1.200 g/cm³; the crystals of the 2S isomer hemihydrate are triclinic, P1, a = 11.505(7) Å, b = 12.192(8) Å, c = 13.123(8) Å; α = 103.35(5)°, β = 100.80(5)°, γ = 90.98(5)°; V = 1756(2) ų, Z = 2, d _calc = 1.127 g/cm³. The molecular structure of the spiroadducts is discussed.     

Complex Interrupted Tetrahedral Frameworks in the Nitridosilicates M7Si6N15 (M=La,Ce, Pr)

A new structure type of nitridosilicates with an interrupted framework has been identified for M₇Si₆N₁₅ with M=La, Ce, and Pr. The materials have been synthesized in a radio‐frequency furnace at temperatures between 1550–1625 °C, starting from the respective metals, metal nitrides, and silicon diimide. The crystal structure of Ce₇Si₆N₁₅ has been determined by using single‐crystal X‐ray diffraction. Besides ordered crystals 1 with a complicated triclinic superstructure and multiple twinning (P , no. 2; a=13.009(3), b=25.483(5), c=25.508(10) Å; α=117.35(3), β=99.59(3), γ=99.63(3)°; V=7114(2) ų; Z=18; R1=0.0411), disordered crystals 2 with identical composition exhibiting a trigonal average structure (R , no. 148) have also been observed (a=43.420(6), c=6.506(2) Å; V=10 623(3) ų; Z=27; R1=0.0309). Pr₇Si₆N₁₅ ( 3 ) and La₇Si₆N₁₅ ( 4 ) are isostructural with 1 as evidenced by twinned single‐crystal data for 3 (P , no. 2; a=12.966(3), b=25.449(10), c=25.459(10) Å; α=117.28(3), β=99.70(4), γ=99.60(4)°; V=7068(4) ų; Z=18; R1=0.0526) and powder diffraction data for 4 (P , no. 2; a=13.109(9), b=25.606(18), c=25.609(18) Å; V=7223(12) ų; Z=18; R_P=0.0194; R_F=0.0936). The crystal structure of M₇Si₆N₁₅ (M=La, Ce, Pr) is built up exclusively of corner‐sharing tetrahedrons that appear as Q²‐, Q³‐, and Q⁴‐type tetrahedrons forming different ring sizes within a less condensed three‐dimensional network. Among the characteristic structural motifs are saw‐blade‐shaped 12‐rings and finite chains consisting of four corner‐sharing SiN₄ tetrahedrons. High‐resolution transmission electron micrographs indicate both ordered and disordered crystallites. In the diffraction patterns of disordered rhombohedral crystals, diffuse maxima appear in reciprocal space at those positions in which sharp superstructure reflections are found in the case of the respective ordered crystallites. Magnetic susceptibility measurements of Ce₇Si₆N₁₅ show paramagnetic behavior with an experimental magnetic moment of 2.29 μ_B per Ce, thereby corroborating the existence of Ce³⁺.     

Hydroxo‐bridged Tetranuclear CuII Complexes: {[Cu(bpy)(OH)]4Cl2}Cl2 · 6 H2O and {[Cu(phen)(OH)]4(H2O)2}]Cl4 · 4 H2O

The blue tetranuclear Cu^II complexes {[Cu(bpy)(OH)]₄Cl₂}Cl₂ · 6 H₂O ( 1 ) and {[Cu(phen)(OH)]₄(H₂O)₂}Cl₄ · 4 H₂O ( 2 ) were synthesized and characterized by single crystal X‐ray diffraction. ( 1 ): P 1 (no. 2), a = 9.240(1) Å, b = 10.366(2) Å, c = 12.973(2) Å, α = 85.76(1)°, β = 75.94(1)°, γ = 72.94(1)°, V = 1152.2(4) ų, Z = 1; ( 2 ): P 1 (no. 2), a = 9.770(3) Å, b = 10.118(3) Å, c = 14.258(4) Å, α = 83.72(2)°, β = 70.31(1)°, γ = 70.63(1)°, V = 1252.0(9) ų, Z = 1. The building units are centrosymmetric tetranuclear {[Cu(bpy)(OH)]₄Cl₂}²⁺ and {[Cu(phen)(OH)]₄(H₂O)₂}⁴⁺ complex cations formed by condensation of four elongated square pyramids CuN₂(OH)₂L^ap with the apical ligands L^ap = Cl, H₂O, OH. The resulting [Cu₄(μ₂‐OH)₂(μ₃‐OH)₂] core has the shape of a zigzag band of three Cu₂(OH)₂ squares. The cations exhibit intramolecular and intermolecular π‐π stacking interactions and the latter form 2D layers with the non‐bonded Cl^– anions and H₂O molecules in between (bond lengths: Cu–N = 1.995–2.038 Å; Cu–O = 1.927–1.982 Å; Cu–Cl^ap = 2.563; Cu–O^ap(OH) = 2.334–2.369 Å; Cu–O^ap(H₂O) = 2.256 Å). The Cu…Cu distances of about 2.93 Å do not indicate direct interactions, but the strongly reduced magnetic moment of about 2.74 B.M. corresponds with only two unpaired electrons per formula unit of 1 (1.37 B.M./Cu) and obviously results from intramolecular spin couplings (χ_m(T‐θ) = 0.933 cm³ · mol^–1 · K with θ = –0.7 K).     

Three Ternary Rare Earth(III) Complexes Based on 3‐[(4,6‐Dimethyl‐2‐pyrimidinyl)thio]‐propanoic Acid and 1,10‐Phenanthroline: Synthesis,Crystal Structure and Antioxidant Activity

Three ternary rare earth [Nd^III ( 1 ), Sm^III ( 2 ) and Y^III ( 3 )] complexes based on 3‐[(4,6‐dimethyl‐2‐pyrimidinyl)thio]‐propanoic acid (HL) and 1,10‐phenanthroline (Phen) were synthesized and characterized by IR and UV/Vis spectroscopy, TGA, and single‐crystal X‐ray diffraction. The crystal structures showed that complexes 1 – 3 contain dinuclear rare earth units bridged by four propionate groups and are of general formula [REL₃(Phen)]₂ · nH₂O (for 1 and 2 : n = 2; for 3 : n = 0). All rare earth ions are nine‐coordinate with distorted mono‐capped square antiprismatic coordination polyhedra. Complex 1 crystallizes in the monoclinic system, space group P2₁/c with a = 16.241(7) Å, b = 16.095(7) Å, c = 19.169(6) Å, β = 121.48(2)°. Complex 2 crystallizes in the monoclinic system, space group P2₁/c with a = 16.187(5) Å, b = 16.045(4) Å, c = 19.001(4) Å, β = 120.956(18)°. Complex 3 crystallizes in the triclinic system, space group P1 with a = 11.390(6) Å, b = 13.636(6) Å, c = 15.958(7) Å, α = 72.310(17)°, β = 77.548(15)°, γ = 78.288(16)°. The antioxidant activity test shows that all complexes own higher antioxidant activity than free ligands.     

Bis[N,N′‐bis(2‐nitrocinnamaldehyde)phenylenediimine]copper(I) Perchlorate

The complex [Cu(nitroca₂ph)₂]ClO₄, where nitroca₂ph is N,N′‐bis(2‐nitrocinnamaldehyde)phenylenediimine, crystallizes in the triclinic space group with a = 13.167(1), b = 13.209(1), c = 14.465(1) Å, α = 83.209(9)°, β = 68.438(2)°, γ = 70.803(2)°, V = 2209.4(3) ų, Z = 2, D_calc = 1.527 mg/m³. The coordination polyhedron about the Cu(I) atom is best described as a distorted tetrahedron. 2‐nitroca₂en acts as a bidentate ligand coordinating via two N atoms to the copper. The four Cu–N distances are 2.04 (2), 2.038(2), 2.046(2), and 2.062(2) Å.