Uncommon Behavior of Copper(I) Tetrafluoroborate and Perchlorate in [Cu(DAF)(H2O)]BF4and [Cu(DAF)(ClO4)] π-Complexes (DAF—Diallyl Formamide)

Crystals of [Cu(DAF)(H₂O)]BF₄(I) and [Cu(DAF)(ClO₄)] (II) (DAF is diallyl formamide) were synthesized by an alternate-current electrochemical method, and their structures were determined (MoK radiation, 1247 and 859 independent reflections with I 2(I), R= 0.043 and 0.032 for Iand II, respectively). The complexes crystallize in space group P2₁/n, Z= 4. For I, a= 10.782(3) Å, b= 12.096(5) Å, c= 9.185(3) Å, = 103.62(3)°, and V= 1164.2(7) ų; for II, a= 10.064(3) Å, b= 10.753(6) Å, c= 10.002(3) Å, = 87.52(4)°, and V= 1081.4(8) ų. The copper atom in structures Iand IIcoordinates both C=C bonds in one DAF molecule and oxygen atom of the amide group of another DAF molecule, as well as an oxygen atom of H₂O (in I) or ClO₄(in II) in the axial position. The uncommon behavior of the anions in structures Iand IIis explained by their different values of Pierson hardness.     

Metal chelates with some cellulose derivatives; part IV. Structural chemistry of HEC complexes

Reactions of hydroxyethyl cellulose (HEC) with Cr ^III, Ni^II, Co^II, or Cu^II chlorides in aqueous medium yielded complexes with formulae [M(HEC)Cl _m .n H ₂O], wherem =1 or 2 and n=2 or 3. HEC acted as a uninegatively charged bidentate ligand in the case of Cr^III and Ni^II, and as a neutral ligand in the case of Co^II and Cu^II complexes. The spectra showed that the binding sites in Cr^III and Ni^II complexes were the ether oxygen between two ethoxyl groups and the oxygen of the hydroxyl group; while in the Co^II and Cu^II complexes the binding sites were the oxygen of ethoxyl groups and the primary alcoholic O atom of glucopyranose rings. These complexes would most likely exhibit octahedral geometry with Cr^III, Ni^II, and Co^II, but square planar configuration in the case of the Cu^II complex. The ligand parameters of the Cr^III, Ni^II, and Co^II metal chelates were calculated in different solvents and at different temperatures. The thermal stability of the above complexes was investigated and the overall thermodynamics functions G⁰, H⁰, and S⁰, associated with complex formation, were estimated.     

Synthesis and characterization of complexes of the first transition series cations with 2,2′-biimidazole and 2,2′-biimidazolate

Mononuclear [M(hfacac)₂(H₂biim)] complexes, where M = Mn^II, Fe^II, Co^II, Ni^II, Cu^II or Zn^II, hfacac = hexafluoroacetylacetonate, H₂biim = 2,2-biimidazole; dinuclear K₂[M₂(acac)₄(-biim)] (M = Cu^II or Zn^II) and tetranuclear K₂[M₄(acac)₈( ₄-biim)] (M = Co^II or Ni^II) complexes have been prepared and characterized by chemical analysis, conductance measurements, i.r., electronic and e.p.r. spectroscopies and by magnetic susceptibility measurements (in the 2–300 K range). Mn^II, Fe^II and Co^II are in a high spin state. The e.p.r. spectra of Cu^II and Mn^II compounds have been recorded.     

Palladium Clusters Pd4(SEt)4(OAc)4and Pd6(SEt)12: Structure and Properties

Palladium clusters Pd₄(SEt)₄(OAc)₄(I) and Pd₆(SEt)₁₂(II) were synthesized and studied. Their structure was determined by X-ray diffraction analysis. For I, a= 9.774(2) Å, b= 10.821(2) Å, c= 13.061(3) Å, = 92.88(3)°, V= 1379.6(5) ų, (calcd.) = 2.182 g/cm³, space group P2₁/n, Z= 4, N _ref= 1558, and R= 0.031; for II, a= 10.581(1) Å, b= 10.584(2) Å, c= 11.478(2) Å, = 101.62(1)°, = 104.95(1)°, = 106.74(1)°, V= 1135.2(4) ų, (calcd) = 2.007 g/cm³, space group P1, Z= 1, N _ref= 2828, and R= 0.022. In cluster I, four Pd atoms form a planar cycle. The neighboring palladium atoms are bound by two acetate or by two mercaptide bridges, the Pd···Pd distances being 3.036–3.195 Å. In cluster II, Pd atoms form a planar six-membered cycle with Pd···Pd distances of 3.083–3.127 Å. The neighboring palladium atoms are bound by two mercaptide bridges. The formation of analogous clusters in solution was confirmed by IR spectroscopy.     

The Crystal Structures of Rubidium and 4-Amino-1,2,4-Triazolium Tetrafluoroantimonates(III)

The crystal structures of complex antimony(III) fluorides RbSbF₄ (I) and (C₂N₄H₅)SbF₄ (II) were determined. The crystals of I and II are monoclinic; for I: a = 4.628(1) Å, b = 6.167(1) Å, c = 7.922(1) Å, = 100.582(3)°, V = 222.24(7) ų, Z = 2, (calcd.) = 4.23 g/cm³, (exp.) = 4.25 g/cm³, F(000) = 248, space group P2₁/m, R = 0.0395; for II: a = 4.678(1) Å, b = 7.339(4) Å, c = 10.185(1) Å, = 90.88(2)°, V = 349.6(2) ų, Z = 2, (calcd.) = 2.69 g/cm³, (exp.) = 2.70 g/cm³, F(000) = 264, space group P2₁. The structure of I is formed by Rb⁺ cations and [SbF₄] ^n– _n anionic chains composed of SbF₅E octahedra with two bridging fluorine atoms. The structure of IIis formed by (C₂N₄H₅)⁺ cations and isolated [SbF₄]^– anions in which the antimony polyhedra are SbF₄E trigonal bipyramids. The relationship between the crystal structures and electrophysical and biological properties of single-charged cation tetrafluoroantimonates(III) was studied.     

Solochrome Black P.V. as a new reagent in chelatometry

Summary Solochrome Black P.V. has proved to be a suitable metallochromic indicator in direct titrations of Mg, Zn, Cd and Mn^II with EDTA or in back titrating Pb, M and Co at p_H 10. By its aid together with the application of masking agents as potassium cyanide and ammonium fluoride and the mercuric nitrate procedure, fifteen binary mixtures were analysed using simple procedures which gave precise, reproducible and highly accurate results. It can be used as a substitute for Eriochrome Black T in determining micro and milligram amounts of the above mentioned cations.Part I: Khalifa, H., and S. W. Bishra: Z. analyt. Chem. 183, 108 (1961).     

Cacotheline as a specific reagent for the detection of iron(II)

Summary Cacotheline gives a blue colour with iron (II) in the p_H range 5.2 to 7.8 in the presence of a suitable complexing agent like sodium oxalate or sodium citrate. The blue colour is not stable in air. It has now been shown that if the test is carried out in a Thunberg tube with the exclusion of air, the colour is quite stable at p_H 7.4 (McIlvaine buffer). This reaction affords a sensitive test for iron (II). In a test tube reaction, the limit of identification has been found to be 11 g in about 5 ml of solution. On a spot plate, the limit of identification has been found to be 0.5 g and the dilution limit 1100,000. On special Whatman spot filter paper No. 542, the identification limit has been found to be 0.3 g and the dilution limit 1166,000. The test can also be applied to iron (III) after reduction with sodium oxalate under a Philips' Repro lamp. Reducing agents like sodium sulphite, sodium thiosulphate, sodium hypophosphite, thiourea and ascorbic acid which reduce cacotheline to a pink coloured compound, just like iron (II) (in the presence of oxalate, etc.) in an acid medium, do not give the blue colour with cacotheline in the basic p_H range; Sb^III, As^III, U^III, U^IV, Cu^I, Cr^II, Ce^III, Sn^II, V^III, Ge^II, and Ti^III also do not give the blue colour with cacotheline under the conditions where iron (II) answers the test. The colour reaction now developed appears to be quite specific for iron (II).In conclusion, two of us, V. Narayana Rao and Mrs G. Somidevamma desire to thank the Ministry of Education, Government of India for the award of Research Scholarships.See also Z. analyt. Chem. 152, 346 (1956).     

Crystal Structures of Ammonium and Cesium Pentadecafluorotetraantimonates(III)

Antimony(III) fluoride complexes with compositions (NH₄)₃Sb₄F₁₅(I) and Cs₃Sb₄F₁₅(II) are structurally characterized. Crystals Iare triclinic: a= 8.317(3) Å, b= 10.419(6) Å, c= 10.826(3) Å, = 63.71(4)°, = 73.24(3)°, = 77.42(5)°, Z= 2, _calcd= 3.42 g/cm³, _exp= 3.45 g/cm³, space group P , R= 0.051; crystals IIare monoclinic: a= 8.079(2) Å, b= 29.116(8) Å, c= 8.162(2) Å, = 117.08(2)°, Z= 4, _calcd= 4.549 g/cm³, _exp= 4.50 g/cm³, space group P2₁/c, R= 0.036. Structure Iis composed of SbF₄E and SbF₅E polyhedra combined into tetranuclear chains; crystals IIconsist of SbF₄E polyhedra, two of which form a dimer Sb₂F₇E₂, while the other two are isolated (E is the antimony lone electron pair).     

Synthesis and Crystal Structure of Acid Phosphites RbH2PO3, CsH2PO3, and TlH2PO3

The reaction of Rb, Cs, or Tl carbonates with a solution of phosphorous acid gave crystalline acid phosphites RbH₂PO₃(I), CsH₂PO₃(II), and TlH₂PO₃(III). The crystal structures of the compounds were studied by a single-crystal X-ray diffraction analysis at 150 K: I, monoclinic system, a= 7.530(2) Å, b= 8.634(2) Å, c= 12.426(2) Å, = 102.46(3)°, V= 788.8(3) ų, Z= 8, space group P2₁/c, R ₁= 0.0409; II, monoclinic system, a= 7.930(2) Å, b= 8.929(2) Å, c= 13.163(3) Å, = 104.84(3)°, V= 900.9(4) ų, Z= 8, space group P2₁/c, R ₁= 0.0239; III, orthorhombic system, a= 6.603(1) Å, b= 6.785(1) Å, c= 8.836(2) Å, V= 395.9(1) ų, Z= 4, space group Pna2₁, R ₁= 0.0350. The PHO₃tretrahedra in structures I–IIIare joined via hydrogen bonds into infinite zigzag-like chains [HPHO₃] ^n– _n, which form layers alternating with layers of metal cations. The layers of anionic chains are wavelike in Iand IIand planar in III. Apparently, IIIis not isostructural to Ior IIdue to the fact that Tl(I) has a stereochemically active pair of electrons.     

Molecule-Based Magnets with 1D Chain Structure of Bifurcated H-Bonding: Syntheses,Structure, and Magnetic Properties

Two complexes [PyH][Ni(Mnt)₂] (I) and [QlH][Ni(Mnt)₂] (II) (Mnt^2– = maleonitriledithiolate, [PyH]⁺ = pyridinium, [QlH]⁺ = quinolinium) were synthesized and characterized by elemental analysis and IR spectra. ESR spectra of polycrystalline samples collected at room temperature are isotropic with g = 2.039 for Iand anisotropic with g _z = 1.997, g _y g _x = 2.102 (g _av = 2.068) for II. The magnetic susceptibility data of I and II have been measured in the temperature range of 2–300 K. The results obtained suggest the antiferromagnetic coupling interactions between neighboring Ni³⁺ ions for I and ferromagnetic coupling interactions for II, respectively. Based on the crystal structure analysis of I, the magnetic properties of two complexes were discussed.     

Crystal Structure of Thallium Tridecafluorotetraantimonate(III) TlSb4F13

The crystal structure of thallium fluoroantimonate(III) complex TlSb₄F₁₃ (I), which is isostructural to KSb₄F₁₃ (II), is determined. Crystals I are tetragonal: a = 9.634(2) Å, c = 6.590(2) Å, V = 611.7(2) ų, Z = 2, (calcd) = 5.094 g/cm³, F(000) = 804.0, space group I4¯. The structure consists of tetrameric [Sb₄F₁₃]^– anions formed by SbF₃ groups connected by the fluoride ion and the l⁺ cations.     

Tetrabutylammonium Salts of Ruthenium(II) Nitroso Complexes

The paper describes synthesis of (nBu₄N)₂[RuNOCl₅](I), (nBu₄N)₂[RuNOCl₄OH](II), (nBu₄N)₂×[RuNOCl₄OH]·6H₂O (III), and (nBu₄N)₂[RuNOCl₅]· 2(nBu₄N)₂[RuNOCl₄(H₂O)]·2H₂O (IV). The complexes were studied by IR spectroscopy and powder Xray and crystal Xray analyses. The structures are built up of [RuNOCl₅]^2- (I, IV), [RuNOCl₄OH]^2- (II, III), and [RuNOCl₄(H₂O)]^- (IV) complex anions, (nBu₄N)⁺ cations, and crystal water molecules (III, IV). The substances are moderately soluble in water; highly soluble in polar organic solvents, such as acetone, ethanol, chloroform, methylene chloride; and almost insoluble in carbon tetrachloride and toluene. Under storage in light, the compounds decompose from the surface; in darkness I and II are stable, whereas III and IV can lose part of the crystal water.     

Structure of Complexes Formed in the CuX2–Cu–N-Allylisoquinolinium Chloride System (X = Cl,Br)

The crystals of N-allylisoquinolinium chlorides of the compositions [C₉H₇N(C₃H₅)]₂Cu^IICl₄ (I), [C₉H₇N(C₃H₅)]Cu^ICl₂ · H₂O (II), and [C₉H₇N(C₃H₅)]Cu^ICl_1.43Br_0.57 · H₂O (III) were prepared by alternating-current electrosynthesis. X-ray diffraction analysis (using diffractometer models DARCH1 for I, STOE for II, and KUMA/CCD for III, MoK radiation) showed that the crystals of I are monoclinic, space group P2₁/n, a = 14.91(1) Å, b = 10.41(1) Å, c = 16.90(1) Å, = 109.73(8)°, V = 2470(8) ų, Z = 4. The crystals of isostructural compounds II and III are triclinic, space group P, Z = 2; crystals II: a = 7.2446(6) Å, b = 7.4379(6) Å, c = 12.110(1) Å, = 80.95(1)°, = 85.55(1)°, = 86.60(1)°, V = 641.8(2) ų; crystals III: a = 7.253(2) Å, b = 7.459(4) Å, c = 12.151(5) Å, = 80.82(4)°, = 83.73(3)°, = 86.81(4)°, V = 644.6(9) ų. The structure of I is composed of Cu^IICl₄ ^2– tetrahedra and N-allylisoquinolinium cations united by C–H···Cl hydrogen bonds in corrugated layers. The crystal structures of -complexesII and III are built of [C₉H₇(C₃H₅)]₂Cu₂ ^IX₄ dimers, which form layers along the c axis due to the C–H···X hydrogen bonds. An important role in the structure formation is played by water molecules, which crosslink the organometallic layers to form a three-dimensional framework through the O–H···X contacts.     

Copper(II) Complexes with N-(3-Hydroximino-2-methylbutan-2-yl)methylamine (HL): Synthesis and Properties. Crystal and Molecular Structures of [Cu(HL)Cl2] and [Cu(HL)(H2O)2SO4]n

Paramagnetic copper(II) complexes with N-(3-hydroximino-2-methylbutan-2-yl)methylamine (HL), namely, Cu(HL)Cl₂(I), Cu(HL)(SO₄) · 2H₂O (II), and Cu(HL)(NO₃)₂(III), were obtained. The crystal structures of I and II were determined. The blue crystals of these compounds are monoclinic. For I(C₆H₁₄Cl₂CuN₂O): a = 8.820(1) Å, b = 6.511(1) Å, c = 18.255(2) Å, = 92.86(1)° V = 1047.0(2) ų, space group P2₁/c, _calcd = 1.679 g/cm³, Z = 4 for R ₁ = 0.0250; for II(C₆H₁₈CuN₂O₇S): a = 9.999(2) Å, b = 9.927(2) Å, c = 12.963(3) Å, = 106.37(3)°, V = 1234.5(4) ų, space group P2₁/c, _calcd = 1.753 g/cm³, Z = 4 for R ₁ = 0.0324. Crystals of I have a molecular structure. The Cu coordination polyhedron is a square bipyramid (2N + 2Cl + Cl + Cl) due to additional contacts with two Cl atoms from the neighboring molecules. Structure II is built from polymeric chains. The environment of the Cu atom is a distorted cis-octahedron (2N + 2O(H₂O) + 2O(SO₄)). Complexes I–IIIare characterized by IR and EPR spectroscopy.     

N-Ferrocenylcarbonyl-N′-benzoylhydrazine and its transition metal(II) complexes

Summary A new ferrocene derivative, N-ferrocenylcarbonyl-N-benzoylhydrazine (H₂FB) and its transition metal complexes, [M(FB)]₂·H₂O (M = Mn^II, Co^II, Cu^II, Zn^II, Cd^II or Hg^II) and M(HFB)₂·nH₂O (M = Mn^II or Cd^II) were prepared by reacting H₂FB with the metal(II) acetates and characterized by elemental analyses, i.r. and u.v. spectroscopy and t.g.a. H₂FB appears to act as a tetradentate ligand, coordinating to the metal through the nitrogen enolic oxygen atoms.     

Crystal Structure of 1,10-Diazonia-18-crown-6 Bis(hydrogen oxalate) and 1,10-Diazonia-18-crown-6 Oxalate Dihydrate

An X-ray diffraction study has been performed to study the crystal structure of 1,10-diazonia-18-crown-6 bis(hydrogen oxalate) [H₂DA18C6]²⁺·2C₂HO ₄ ^- (I) and 1,10-diazonia-18-crown-6 oxalate dihydrate [H₂DA18C6]²⁺·2C₂O ₄ ^- ·2H₂O (II). Crystals I are triclinic: space group , a = 7.825, b = 7.861, c = 9.349 , = 97.28, = 110.22, = 99.12°, Z = 1. Crystals II are monoclinic: space group P2 ₁ /n, a = 8.783, b = 10.640, c = 10.225 , = 97.04°, Z = 2. The structures of I and II were solved by direct methods and refined by the full-matrix least-squares procedure anisotropically to R = 0.036 (I) and 0.042 (II) for all 2206 (I) and 1990 (II) unique reflections measured (CAD-4 automatic diffractometer, CuK ). In the crystal structures, the ionic complexes (salts) I and II are not individual guest–host complex molecules but are parts of complex (infinite in two directions) three-dimensional layers of H-bonded molecular anions and DA18C6 dications (and water molecules in II). In structures I and II, the centrosymmetric DA18C6 dications have different conformations: two-angle in I and four-angle in II. The unusual four-angle conformation of the DA18C6 dication was found for the first time.     

Transition metal complexes with a polydentate Schiff base derived from 3-formylsalicylic acid and 1,2-bis(o-aminophenylthio)ethane

The reaction of 3-formylsalicylic acid with 1,2-bis(o-aminophenylthio)ethane yielded a Schiff base with eight donor centres N₂S₂O₄ of which the inner compartment is of an N₂S₂O₂ type and the outer is of the O₂O₂ type. The base forms several mononuclear homo- and hetero-dinuclear complexes: e.g. mononuclear Cu^II, Ni^II and dinuclear Cu^II, Ni^II, UO₂ ^VI complexes. Hetero-dinuclear complexes {[M]M}, where M = the inner metal ion Cu^II, Ni^II and M = the outer metal ion Pd^II, UO₂ ^VI are also reported. The complexes were characterised by elemental analyses, spectral, thermal and magnetic measurements. Dicopper and dinickel complexes exhibit subnormal magnetic moments showing spin pairing between two metal centres, via the phenolato oxygen, whereas other mono-copper and mono-nickel complexes (both mononuclear and hetero-dinuclear) show the expected magnetic behaviour for 1e and 2e, respectively. The e.s.r. spectra of copper complexes also support the above behaviour.     

Comparative stability constants for metal ions with tetraazamacrocycles of various ring sizes carrying a single amine or carboxylate pendant group

Acid dissociation constants for a series of tetraazamonocycloalkanes of {13}–{15} membered ring sizes, as well as for a related reinforced {15R} tetraazabicycloalkane, each with one primary amine or carboxylate C-pendant, are reported. Further, formation constants with the metal ions Zn^II, Cd^II, Pb^II, Hg^II, Mn^II and Co^II have been determined. The ligands differ in their selection of metal ions, reflected in the formation constants for 1:1 complexation (K _ML). Differences arise in part from the increasing ring size or rigidity and also from the availability of potential pendant O-donors versus N-donors in stepping from amine to carboxylate pendant ligands, implying a role for the pendants in binding the metal ions.     

Nickel(II) Diisobutyldithiophosphinate Complexes with Hexamethylenetetramine and Triethylenediamine: Synthesis and Properties. Crystal and Molecular Structure of [Ni2(C6H12N4){(i-C4H9)2PS2}4]

The paramagnetic compounds [Ni₂(HMTA)(i-Bu₂PS₂)₄] (I) and [Ni₂(TEDA)(i-Bu₂PS₂)₄] (II) (_eff = 3.11 and 3.23 _B, respectively) were synthesized by reacting diamagnetic Ni(i-Bu₂PS₂)₂ with hexamethylenetetramine (HMTA) and triethylenediamine (TEDA) in ethanol. The crystal structure of I was established by single-crystal X-ray diffraction analysis (CAD4 diffractometer, MoK radiation, 1483 F _hkl, R = 0.0648). The crystals are monoclinic: a = 35.212(7) Å, b = 9.313(2) Å, c = 22.622(5) Å; = 129.97(3)°, V = 5685(2) ų, Z = 4, (calcd) = 1.281 g/cm³, space group C2/c. The structure is built of discrete binuclear molecules. The coordination polyhedron of the Ni atom is a distorted tetragonal pyramid with four S atoms of two bidentate cyclic ligands i-Bu₂PS₂ ^– in the base and the N atom of the bidentate bridging ligand HMTA at the axial vertex. Complexes I and II have similar electronic reflection spectra, which agrees with the C _4v symmetry of the ligand field.     

Coordination compounds of hydrazine derivatives with transition metals. Part 26. Coordination properties of α-diketone and α-ketoaldehyde bishydrazones derived from hydrazine-S-methylcarbodithioate

Summary Metal(II) chelates with -diketone and -ketoaldehyde bishydrazones derived from hydrazine-S-methylcarbodithioate with the general formula M[-dik(hydth)₂-2H] (M=Zn^II, Cd^II, Ni^II, Cu and Pd^II) were prepared and characterized by i.r., electronic and mass spectra as well as magnetic properties. The Ni^II, Zn^II and Cd^II chelates are most probably pentacoordinated dimers whereas the Cu^II chelates are polymeric through Cu-S linkages. The Pd^II chelates are square planar monomers.