Crystal structures of bis(AZIDO)bis(2-morpholin-4-ylethylamino)copper(II) and bis{2,4-dibromo-6-[(2-morpholin-4-ylethylimino)methyl] phenolato}copper(II)

Two new copper(II) complexes [Cu(MEA)₂(N₃)₂] (1) and [Cu(BMP)₂] (2), where MEA and BMP are 2-morpholin-4-ylethylamine and 2,4-dibromo-6-[(2-morpholin-4-ylethylimino)methyl]phenolate respectively, are prepared and characterized using elemental analysis, FT-IR spectroscopy, and X-ray single crystal diffraction. The crystal of 1 belongs to the triclinic system, space group P-1, with a = 6.661(2) Å, b = 8.440(3) Å, c = 8.913(3) Å, α = 102.032(3)°, β = 107.899(2)°, γ = 98.242(3)°, V = 454.6(3) ų, Z = 1, D _c = 1.490 g/cm³, R ₁ = 0.0226, and wR ₂ = 0.0564. The crystal of 2 belongs to the monoclinic system, space group P2₁/c, with α = 7.0707(7) Å, b = 15.438(1) Å, c = 14.227(1) Å, β = 96.659(2)°, V = 1542.5(3) ų, Z = 2, D _c = 1.821 g/cm³, R ₁ = 0.0437, and wR ₂ = 0.1041. In each complex, the Cu atom is in a square planar coordination. The molecules of 1 are linked through intermolecular N-H...N and N-H...O hydrogen bonds to form layers parallel to the ab plane. The molecules of 2 are linked through intermolecular C-H...Br hydrogen bonds to form a 3D network.     

Thiourea-halide lattices. Part 1. Crystal structures of (n-C4H9)4N+F−·3(NH2)2CS, (n-C4H9)3(CH3) N+X−·2(NH2)2CS (X = Cl,Br), and (n-C3H7)4N+I−·(NH2)2CS

The title complexes (1, X = F;2, X = C 1; 3, X = Br and isomorphous with2; 4, X = I) have been prepared and characterized by X-ray crystallography. Crystal data, MoKα radiation:1, space groupCc,Z =4,a = 12.017(3),b = 14.263(5),c = 17.210(7) Å,β = 103.06(2)°, andR _F =0.053 for 2044 observed data;2, space groupCc,Z = 4,a = 12.817(3),b = 11.072(2),c = 16.781(5) Å,β =90.74(2)°,R _F = 0.044 for 2249 data;3,a = 12.873(4),b = 11. 119(2),c = 16.957(2) Å,β = 89.11(2)°,R _F = 0.049 for 2059 data;4, space groupP2₁/n,Z = 4,a = 8.858(2),b = 14.358(3),c = 15.379(3) Å,β = 93.88(1)°,R _F = 0.068 for 3119 data. In all four structures each thiourea molecule interacts with adjacent thiourea molecules via N-H ... S hydrogen bonds to give a ribbon-like arrangement, and also forms a pair of ‘chelating’ N-H ... X hydrogen bonds with a halide ion, resulting in an anionic framework (in1–3) or composite ribbon (in4) as a component in the crystal packing. The measured ranges of N... X distances are: 2.819(5)-2.994(7) Å for1, 3.252(3)-3.291(3)Å for 2, 3.353(6)-3.459(6)Å for3, and 3.564(5)-3.680(5) Å for 4.     

Synthesis and crystal structure of Mn(II) and Hg(II) compounds and solution studies of Mn(II), Zn(II), Cd(II) and Hg(II) compounds based on piperazinediium pyridine-2,3-dicarboxylate

Novel metal organic frameworks including {(pipzH₂)[Mn(py-2,3-dc)₂]·7.75H₂O}_n, 1, {(pipzH₂)[Zn(py-2,3-dc)₂]·4H₂O}_n, 2, [Cd(py-2,3-dc)(H₂O)₃]_n, 3 and {(pipzH₂)[Hg₄Cl₁₀]}_n, 4, in which pipz is piperazine and py-2,3-dcH₂ is pyridine-2,3-dicarboxylic acid were synthesized applying a proton transfer ion pair i.e. (pipzH₂)(py-2,3-dcH)₂ and corresponding metallic salts and studied by IR, ¹H NMR, ¹³C NMR spectroscopy and single crystal X-ray diffractometry. The space group of compounds 1 and 4 are P2₁/c and C2/c of monoclinic system, respectively. The crystal dimensions are a = 20.108(2) Å, b = 19.910(2) Å, c = 12.997(1) Å, β = 94.354(2)° for 1 and a = 15.940(1) Å, b = 11.2690(9) Å, c = 11.1307(9) Å, β = 90.685(2)° for 4. The crystal structures of 2 and 3 have been reported previously. However, their solution studies are discussed here. The compounds had all polymeric structures. Although Zn^II, Cd^II and Hg^II were elements of the same group, their behavior against the ion pair was essentially different. Various supramolecular interactions mainly hydrogen bonds of the type O-H?O, N-H?O, C-H?O, N-H…Cl and C-H?Cl were observed in the structures. There was an unusual and huge water cluster in the structure of compound 1. The solution states of compounds 1–4 were studied and reported. The protonation constants of pipz and py-2,3-dc, the py-2,3-dc/pipz proton transfer equilibrium constants and stoichiometry and stability of the system with Mn²⁺, Zn²⁺, Cd²⁺ and Hg²⁺ ions in aqueous solution were investigated by potentiometric pH titrations.     

Acid Co(II) and Ni(II) trifluoroacetate complexes: Synthesis and crystal structure

Anhydrous and partially hydrated acid trinuclear trifluoroacetates of divalent transition metals of the composition [M₃(CF₃COO)₆(CF₃COOH)₆)](CF₃COOH) and [M₃(CF₃COO)₆(CF₃COOH)₂(H₂O)₄)](CF₃COOH)₂, respectively, where M = Co (I, III) Ni (II, IV), were synthesized and studied by X-ray diffraction. Complexes I and II were obtained by crystallization from solutions of M(CF₃COO)₂ · 4H₂O in trifluoroacetic anhydride; complexes III and IV were synthesized under the same conditions with the use of 99% trifluoroacetic acid as a solvent. Crystals I are triclinic: space group $P\bar 1$ , a = 13.199(6) Å, b = 14.649(6) Å, c = 15.818(6) Å, α = 90.04(4)°, β = 114.32(4)°, γ = 108.55(4)°, V = 2611.3(19) ų, Z = 2, R = 0.0480. Crystals II are trigonal: space group $R\bar 3$ , a = 13.307(2) Å, c = 53.13(1) Å, V = 8148(2) ų, Z = 6, R = 0.1112. Crystals III are triclinic: space group $P\bar 1$ , a = 9.001(8) Å, b = 10.379(9) Å, c = 12.119(9) Å, α = 83.67(5)°, β = 72.33(5)°, γ = 83.44(5)°, V = 1068.3(15) ų, Z = 1 Å, R = 0.1031. Crystals IV are triclinic: space group $P\bar 1$ , a = 9.121(18) Å, b = 10.379(2) Å, c = 12.109(2) Å, α = 84.59(3)°, β = 72.20(3)°, γ = 82.80(3)°, V = 1080.94(40) ų, Z = 1, R = 0.0334.     

Heteroligand zinc(II) and copper(II) complexes with naphthylacetic acid and monoethanolamine: Syntheses and crystal structures

New heteroligand Cu(II) and Zn(II) complexes with the α-naphthylacetic acid anion (NAA) and monoethanolamine (MEA), [M(NAA)₂(MEA)₂] (M = Cu²⁺, (I), Zn²⁺ (II)), are synthesized. The crystal structures of the obtained complexes are determined by X-ray diffraction analysis (CIF files CCDC 984097 (I) and 930946 (II)). The crystals are monoclinic, for I: a = 18.8140(9) Å, b = 4.82500(14) Å, c = 16.0360(7) Å, β = 115.135(6)°, V = 1317.87(11) ų, space group P2₁/c, Z = 2; for II: a = 32.9760(14) Å, b = 5.0911(3) Å, c = 15.7994(10) Å, β = 94.418(5)°, V = 2644.6(3) ų, space group C2/c, Z = 4. In the structure of complex I, the Cu²⁺ ion arranged in the symmetry center is coordinated at the vertices of the distorted octahedron by the oxygen atoms of two NAA molecules (Cu-O(2) 2.019(4) Å) and two MEA molecules. The latter is the bidentate-chelating ligand and coordinates the metal through the O and N atoms to form the five-membered metallocycle (Cu-O(3) 2.457(5), Cu-N(1) 1.986(5) Å). In complex II, the Zn atom (on axis 2) is coordinated at the vertices of the distorted tetrahedron by the oxygen atoms of two NAA molecules (Zn-O(2) 1.976(4) Å) and the nitrogen atoms of two MEA molecules (Zn-N 2.034(6) Å). The character of the interaction of coordinated NAA and MEA ligands and methods for packing complexes I and II are considered on the basis of the structural data.     

Cadmium(II) iodide molecular coordination compounds with 4-methylpyridine and 4-methylquinoline

The coordination compounds [CdI₂(4-MePy)₂] (I) and [CdI₂(4-MeQuin)₂] (II) where Quin is quinoline have been synthesized, and their structure has been solved. Crystals of complex I are monoclinic, space group C2/c, a = 13.353(1) Å, b = 16.653(1) Å, c = 14.380 (1) Å, β = 103.17(1)°, V = 3113.5(4) ų, ρ_calcd = 2.425 g/cm³, Z = 8. Crystals of complex II are monoclinic, space group P2₁/c, a = 10.647(1) Å, b = 25.264(1) Å, c = 8.610(1) Å, β = 113.73(1)°, V = 2120.1(3) ų, ρ_calcd = 2.044 g/cm³, Z = 4. Polymer [CdI₂(4-MePy)₂]_∞ chains running in the direction [001] are formed in the structure of complex I. Each of the two crystallographically nonequivalent Cd(1) and Cd(2) atoms are octahedrally surrounded by the four iodine and two nitrogen atoms of the 4-MePy ligand. The Cd(1)?Cd(2) distance in a chain is 4.33 Å. The structure of complex II is built of [CdI₂(4-MeQuin)₂] discrete neutral clusters. The two iodine and two nitrogen atoms of the 4-MeQuin ligand participate in the coordination of the Cd²⁺ ion. The cadmium coordination polyhedron is a distorted tetrahedron (Cd-I_avg, 2.72 Å; Cd-N_avg, 2.30 Å; angles N(I)CdN(I), 98.3–121.8°). The minimum and maximum values correspond to the ICdI angle and NCdN angle, respectively. Complex I is photoluminescent in the solid state at room temperature.     

New complex ytterbium molybdophosphates M 2 I Yb(PO4)(MoO4) (MI = K, Na): Synthesis and structure solution

Complex rare-earth molybdophosphates of sodium and potassium (Na₂Yb(PO₄)(MoO₄) (I) and K₂Yb(PO₄)(MoO₄) (II) are synthesized by solid-phase reactions at 600°C (for I) and 750°C (for II). The molybdophosphates are characterized using powder X-ray diffraction, laser second harmonic generation (SHG), IR spectroscopy, and differential thermal analysis. Their structures are refined using the Rietveld technique. The compounds are isostructural and crystallize in an orthorhombic system (space group Ibca, Z = 8). The unit cell parameters are a = 18.0086(1) Å, b = 12.0266(1) Å, c = 6.7742(1) Å for compound I and a = 19.6646(1) Å, b = 12.0570(1) Å, c = 6.8029(1) Å for compound II. The structures are built of YbO₈ chains extended along axis c and linked into layers through PO₄ tetrahedra. The Na⁺ cations (CN = 6) and the K⁺ cations (CN = 8) reside in the interlayer spaces.     

Crystal structures of allyltriphenyl-phosphonium halogenocuprates(I)

Alternating-current electrochemical synthesis is used to obtain for the first time halogenocuprates of an allyl derivative of phosphonium of the composition (CH₂=CHCH₂(C₆H₅)₃P)CuX₂ (X = Br (I), Cl (II)). Compound I crystallizes in the space group P2₁, a = 9.6341(3) Å, b = 12.4167(4) Å, c = 9.9618(4) Å, β = 117.484(5)°, Z = 2. Compound II crystallizes in the space group P2₁/n, a = 9.9725(5) Å, b = 15.4586(8) Å, c = 13.7557(5) Å, β = 90.429(4)°, Z = 4. In the structures of I and II quasilinear CuX ₂ ^? anions are held by C-H…X hydrogen bonds inside a framework formed by the stacking of phenyl groups from CH₂=CHCH₂(C₆P₅)₃P⁺ cations. Allyl groups are not involved in coordination with copper(I) atoms.     

Synthesis, crystal structure, and structural features of hexa(isothiocyanate)chromates(III) of lanthanum(III) and neodymium(III) complexes with nicotinic acid

[M(C₅H₅NCOO)₃(H₂O)₂][Cr(NCS)₆] · nH₂O complexes, where M = La and n = 2 (1) or M = Nd and n = 1 (2), were synthesized by reacting M(NO₃)₃ (M = La, Nd, K₃[Cr(NCS)₆]) and nicotinic acid (C₅H₅NCOO) in aqueous solution. Their structure was established by IR spectroscopy and X-ray diffraction analysis. The crystals of complexes 1 and 2 are monoclinic, space group P2₁/n, Z = 2; for complex 1, a = 9.66800(10) Å, b = 25.7662(2) Å, c = 15.4843(2) Å, β = 106.4700(10)sO, V = 3698.99(7) ų, ρ_calcd = 1.761 g/cm³; for complex 2, a = 9.53120(10) Å, b = 25.5166(4) Å, c = 15.3843(3) Å, β = 104.9450(10)sO, V = 3614.96(10) ų, ρ_calcd = 1.779 g/cm³. Different hydrate compositions of the given compounds may be due to the specific features of intermolecular interactions in their structures.     

Further studies on the taumerization of the hydrido (alkynyl) cluster Ru3Pt(μ-H) {μ4-ν2-C ≡ C1Bu} (CO)9(L2) to the vinylidene cluster Ru3Pt{μ4-ν2-C ≡ C(H)tBu} (CO)9(L2): X-ray structures of Ru3Pt(μ-H){μ4-ν2-C = C(H)tBu} (CO)9(L2); L2 = dppet,dppp, andS,S-dppb

The first order rate constants for the tautomerization of the hydrio(alkynyl) clusters Ru₃Pt(μ-H){μ₄-ν²-C ≡ C¹Bu}(CO)₉(L₂);1a: L₂ = dppe,1b; L₂ = dppet,1c; L₂ = dppp and1d; L₂ =S,S-dppb to the corresponding vinylidene clusters Ru₃Pt{μ₄-ν²-C = C(H)^tBu}(CO)₉(L₂)2 have been measured, and they follow the orser1d <1a <1b ～1c. The reactions involving1a and1d exhibit an inverse kinetic deuterium isotope effect. The structures of1b, 2b, 2c, and2d were determined by X-ray crystallography, and are compared with those of1a and2a which have been previously reported. Crystal data for1b, space groupPbca,a = 13.338(4) Å,b = 17.771(6) Å,c = 36.092(8) Å,Z = 8,R(R _w) = 0.059(0.058) for 2342 absorption corrected, observed data; for2b, space group P2₁/n,a = 10.566(2) Å,b = 20.234(5) Å,c = 20.270(3) Å,β = 96.11(1)°,Z = 4,R(R _w) = 0.043(0.053) for 5865 absorption corrected, observed data; for2c, space group P2₁/n,a = 14.211(5) Å,b = 19.534(2) Å,c = 15.870(2) Å,β = 100.81(2)°,Z = 4,R(R _w) = 0.055(0.031) for 6566 absorption corrected, observed data: for2d, space group P2₁2₁2₁,a = 12.309(4) Å,b = 19.047(6) Å,c = 19.206(4) Å,Z = 4,R(R _w) = 0.055(0.053) fpr 2151 absorption corrected, observed data. The fluxional behavior of1d and1e (which consists of two interconverting isomers) has been examined by variable temperature¹³C NMR spectroscopy and by³¹P EXSY.     

Synthesis and study of tetraamminecobalt hydrogen hexamolybdometalates(III)

Tetraamminecobalt hydrogen hexamolybdoferrate [Co(NH₃)₄] · H[FeMo₆O₁₈(OH)₆] · 6H₂O (I) and tetraamminecobalt hydrogen hexamolybdogallate(III) [Co(NH₃)₄] · H[GaMo₆O₁₈(OH)₆] · 6H₂O (II) were synthesized and studied by mass spectrometry, thermogravimetry, IR spectroscopy, and X-ray diffraction. Crystals of I and II are monoclinic; a = 16.21 Å, b = 5.43 Å, c = 12.32 Å, β = 119.63°, V = 1092.11 ų, ρ_calcd = 2.21 g/cm³, and Z = 1 for I; a = 16.24 Å, b = 5.59 Å, c = 12.29 Å, β = 119.79°, V = 1064.05 ų, ρ_calcd = 2.15 g/cm³, and Z = 1 for II. Compounds I and II were used as catalysts for soft oxidation of natural gas.     

Structural investigation of ethylenediaminium tetrachloroaurates(III)

The (EnH₂)[AuCl₄]₂·2H₂O (I) and (EnH₂)₂[AuCl₄]Cl₃ (II) (EnH ₂ ²⁺ is diprotonated ethylenediamine) complexes are produced and characterized by elemental and thermogravimetric analysis, X-ray diffraction, IR and Raman spectroscopy. For I, the crystals are monoclinic, crystallize in the space group P2₁/c: a = 7.5870(2) Å, b = 9.5665(2) Å, c = 11.4706(3) Å, β = 107.0480(10)°, V = 795.97(3) ų, Z = 4. For II, the crystals are orthorhombic, crystallize in the space group Pnma: a = 12.7088(3) Å, b = 17.7435(5) Å, c = 7.4992(2) Å, V = 1691.06(8) ų, Z = 8.     

Syntheses, crystal structures, and fluorescence properties of Zinc(II) complexes with multi-dentate Schiff bases

Two new structurally similar mononuclear Schiff base zinc(II) complexes, [ZnBr(ClMP)] (I) and [ZnCl(NMP)] (II) (ClMP = 4-chloro-2-[(3-morpholin-4-ylpropylimino)methyl]phenolate; NMP = 4-nitro-2-[(3-morpholin-4-ylpropylimino)methyl]phenolate), and two new dinuclear Schiff base zinc(II) complexes, [Zn₂(EMP)₂I₂] (III), and [Zn₂(MPA)(CH₃OH)₂(N₃)₂] (IV) (EMP = 5-diethylamino-2-[(2-dimethylaminoethylimino)methyl]phenolate; MPA = N,N′-bis(3-methoxysalicylidene)propane-1,3-diamine), have been prepared and characterized mainly by single-cyrstal X-ray diffraction. Complex I crystallizes in the monoclinic space group P2₁/n with unit cell dimensions: a = 15.116(3), b = 9.465(1), c = 23.714(4) Å, β = 104.358(2)°, V = 3286.9(8) ų, Z = 8, R ₁ = 0.0439, and wR ₂ = 0.0736. Complex II crystallizes in the monoclinic space group P2₁/c with unit cell dimensions: a = 7.253(2), b = 16.652(4), c = 13.568(3) Å, β = 96.600(2)°, V = 1627.8(6) ų, Z = 4, R ₁ = 0.0417, and wR ₂ = 0.0809. Complex III crystallizes in the monoclinic space group C2/c with unit cell dimensions: a = 27.962(2), b = 8.246(2), c = 31.605(3) Å, β = 90.343(2)°, V = 7287.4(15) ų, Z = 8, R ₁ = 0.0721, and wR ₂ = 0.1709. Complex IV crystallizes in the monoclinic space group C2/c with unit cell dimensions: a = 20.483(3), b = 11.344(2), c = 14.909(3) Å, β = 131.650(1)°, V = 2588.6(7) ų, Z = 4, R ₁ = 0.0343, and wR ₂ = 0.0792. Each Zn atom in I and II are four-coordinated in a tetrahedral geometry by the NNO donor set of the Schiff base ligand and one halide atom. The Zn atoms in III are in square pyramidal coordination, and those in IV are in octahedral and tetrahedral coordination. Thermal stability and fluorescence properties of the complexes I and II have also been determined.     

Syntheses and structural characterization of silver(I) complexes with pyridine and carboxylate derivatives

Self-assembly between silver carboxylates with 2-aminopyridine derivatives give two silver(I) complexes, [[Ag(5MP)₂(CNB)] · NH₃ (I) and [Ag(3MP)₂(HMB)] (II), where 5MP, CNB, 3MP, and HMB represent 2-amin-5-methylpyridine, 5-chloro-2-nitrobenzoate, 2-amino-3-methylpyridine, and 2-hydroxy-3-methoxybenzoate, respectively. The crystal structures of the complexes were investigated. The Ag atom in each complex is coordinated by two pyridine N atoms and weakly coordinated by a carboxylic O atom. The crystal of I is triclinic: space group P $ \bar 1 $ , a = 7.562(2), b = 11.708(3), c = 12.933(3) Å, α = 103.378(4)°, β = 93.910(4)°, γ = 99.001(4)°, V = 1093.7(5) ų, Z = 2. The crystal of II is monoclinic: space group C2/c, a = 25.727(5), b = 10.274(2), c = 19.872(4) Å, β = 126.62(3)°, V = 4215.7(15) ų, Z = 4.     

Cu(I) cloride complexes with 4,5-(2-pyridylethylene)dithio-1,3-dithiol-2-thione and triphenylphosphine

Heteroligand binuclear complexes of CuCl with triphenylphosphine and 5-pyridine-2-yl-5,6-dihydro-[1,3]dithiolo[4,5-b][1,4]dithiine-2-thione (L¹) of the compositions [CuCl(PPh₃)(L¹)]₂ (I) and [CuCiL¹]₂ (II) are synthesized and studied by X-ray diffraction method. Crystals I are monoclinic; space group P2₁/n, a=8.9520(18) Å, b=18.926(4) Å, c=16.841(3) Å, β=94.96(3)°, Z=2. The Cu(I) atom has a quasi-tetrahedral surrounding involving the tetraphenylphosphine P atom, the pyridyl N atom of the molecule L¹, and two bridging Cl atoms. Crystals II are monoclinic; space group P2₁/c, a=9.3520(19) Å, b=8.1490(16) Å, c=18.660(4) A, β = 104.43(3)°, Z = 2. Both L¹ ligands in complex II act as bridges. The Cu(I) atom also has a quasi-tetrahedral surrounding formed by the Cl atoms, the pyridyl N atoms and thiol S atom of one L¹ ligand, and the thione S atom of the second L¹ ligand. Similar binuclear complexes with the bridging function of the L¹ ligand were also detected in a solution of II by the ESI method.     

Synthesis and crystal structures of schiff base copper(II) complexes [Cu(L1)(NCS)], [CuBr(L2)], and [CuCl(L3)]

A series of copper(II) complexes, [Cu(L¹)(NCS)] (I), [CuBr(L²)] (II), and [CuCl(L³)] (III), where L¹, L², and L³ are 2,4-dibromo-6-[(pyridin-2-ylmethylimino)methyl]phenolate, 4-chloro-2-[(pyridin-2-ylmethylimino)methyl]phenolate, and 1-[(pyridin-2-ylmethylimino)methyl]-naphthalen-2-ol, respectively, were prepared. The complexes were characterized by elemental analysis, IR spectra, and single crystal X-ray determination. The crystals of the three complexes crystalize in the monoclinic space group P2₁/n. For I, a = 8.127(2), b = 13.077(3), c = 14.967(3) Å, β = 91.975(2)°, V = 1589.8(6) ų, Z = 4. For II, a = 7.736(2), b = 10.613(2), c = 16.199(3) Å, β = 91.130(2)°, V = 1329.8(5) ų, Z = 4. For III, a = 8.062(2), b = 8.599(2), c = 21.087(2) Å, β = 100.338(2)°, V = 1438.1(4) ų, Z = 4. The Cu atom in each of the complexes is in square planar geometry.     

Diaquabromo(18-crown-6)rubidium and triaqua(18-crown-6)barium dibromide monohydrate: Synthesis and crystal structures

Two complexes are synthesized: diaquabromo(18-crown-6)rubidium [RbBr(18-crown-6)(H₂O)₂] (I) and triaqua(18-crown-6)barium dibromide monohydrate [Ba(18-crown-6)(H₂O)₃]²⁺ 2Br^? · H₂O (II). The orthorhombic structure of compound I (space group Pnma, a = 10.124 Å, b = 15.205 Å, c = 12.544 Å, Z = 4) and the monoclinic structure of compound II (space group C 2/c, a = 17.910 Å, b = 10.315 Å, c = 14.879 Å, β = 123.23°, Z = 4) are determined by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.063 (I) and 0.042 (II) for all 2293 (I) and 3363 (II) independent measured reflections (CAD-4 automated diffractometer, λMoK _α). The complex molecule [RbBr(18-crown-6)(H₂O)₂] in compound I and the randomly disordered cation [Ba(18-crown-6)(H₂O)₃]²⁺ in compound II are of the host-guest type: their Rb⁺ or Ba²⁺ cation (its coordination number is nine) is located in the cavity of the 18-crown-6 ligand and coordinated by all six O atoms. In structure I, the coordination polyhedron of Rb⁺ is a distorted hexagonal pyramid with a triple apex at the Br^? ligand and two O atoms of the water molecules. In structure II, the Ba²⁺ polyhedron is a distorted hexagonal bipyramid with one apex at the O atom of the water molecule and the other split apex at two O atoms of water molecules.     

Copper(II) and lead(II) complexes based on 2,3,5,6-tetrakis(2-pyridyl)pyrazine as a polydentate ligand

The Cu(II) complexes [Cu(Tppz)(Dipic)] · 8H₂O (I) and [Pb₂(Tppz)Cl₄] _n (II), where Tppz, H2Dipic are 2,3,5,6-tetrakis(2-pyridyl)pyrazine, dipicolinic acid, respectively, have been synthesized and characterized by elemental analyses, IR, cyclic voltammetry, and electronic spectral studies. Solid state structures of both complexes have been determined by single crystal X-ray crystallography. An ORTEP drawing of two complexes shows that the coordination geometry around the metal center is a distorted octahedron. There are extensive conventional intermolecular O-H…O, N-H…O, and weaker C-H…O and C-H…Cl non-classical hydrogen bonds, which cause the stability of the crystal structure. Crystal data for I: monoclinic, space group: C2/c, a = 35.421(3), b = 8.422(6), c = 22.824(8) Å, β = 101.69(2)°, V = 6668(5) ų, Z = 8. Crystal data for II: triclinic, space group P \(\bar 1\) , a = 7.9534(4), b = 8.8682(5), c = 9.4245(5) Å, β = 95.086(2)°, V = 655.93(6) ų, Z = 2.     

Synthesis, characterization, solvatochromic behavior and crystal structures of complexes [CoIII(salophen)(thioacetamide)2]ClO4 and [CoIII(salophen)(thiobenzamide)2]ClO4

Two new cobalt(III) complexes of the Schiff base N,N′-disalicylidene-1,2-phenylendiimine dianion (salophen), trans- [Co^III(salophen)(ta)₂]ClO₄, (ta = thioacetamide) (1) and trans-[Co^III(salophen)(tb)₂]ClO₄, (tb = thiobenzamide) (2) were synthesized and characterized using single-crystal X-ray diffraction and spectroscopic techniques. Both complexes show solvatochromism in a variety of solvents. Complex (1) crystallized from CHCl₃ as a solvate of orthorhombic symmetry, space group Pca2₁ with a = 17.3480(10) Å, b = 18.7522(10) Å, c = 18.8128(11) Å, α = β = γ = 90°, and Z = 8. The cobalt(III) center lies in a distorted octahedral environment. The crystal structure of (1) consists of two independent [Co^III(salophen)(ta)₂]⁺ cations and ClO₄ ^- anions held together essentially via hydrogen bonds and π-π stacking interactions. Complex (2), forming also a CHCl₃ solvate, crystallized in the monoclinic space group P2₁/n with a = 14.710(3) Å, b = 13.506(3) Å, c = 18.595(4) Å, β = 100.295(4)°, and Z = 4. The geometry around cobalt(III) center is a distorted octahedron. The crystal structure of (2) contains a [Co^III(salophen)(tb)₂]⁺ complex with a remarkably twisted salophen ligand. Both complexes, (1) and (2), contain approximately one disordered CHCl₃ molecule per Co in the solid state.     

New synthetic routes for the preparation of the triangular trinuclear clusters of tungsten-containing bromine atoms as terminal ligands: Structural characterization of [W3S4Br3(depe)3]PF6·0.5C7 H8 and [W3S4Br3(depe)3]Br·2CH3OH

Synthetic methods are reported for the preparation of compounds containing the trinuclear triangular cluster [W₃S₄Br₃(depe)₃[⁺. These involve reactions between WBr₅ and NaB(C₂ H₅)₃H or NaBH₄ as reducing agent in THF, and subsequent addition of methanolic solutions of NaHS and depe ligand. Both compounds, [W₃S₃Br₃(depe)₃]PF₆·0.5C₇H₈,1, and [W₃S₄Br₃(depe)₃]Br·2CH₃OH,2, are characterized by x-ray single crystal studies. Compounds1 and2 crystallize in space group \(P\bar 1\) . For1,a=10.427 (3) Å,b=15.415(4) Å,c=18.140(5) Å, α=79.36(2)°, β=73.59(2)°, γ=81.54(2)°, andV=2734.8(2) ų;R=0.050 and for 2a=10.491(3) Å,b=15.074(3) Å,c=18.246 Å, α=95.76(2)°, β=105.82(2)°, γ=98.18(2)°, andV=2718.4(3) ų;R=0.081. The two cations in1 and2 possess C₃ symmetry. The W-W distances are in the range 2.783?2.891 Å (for1) and 2.778?2.785 Å (for2) and the average W-Br distances in1 and2 are 2.616[2] Å and 2.594[4] Å, respectively. Each metal atom in the [W₃S₄Br₃(depe)₃]⁺ ions is attached to one capping sulfur atom, two bridging sulfur atoms, one bromine atom, and one chelating depe ligand. One P atom in depe ligand istrans to μ₃-S and the otherP atom istrans to a μ₂-S atom. UV-Vis and NMR spectra for these compounds are also reported.