The N(4S) + N2O(X̃1∑) reaction

The title reaction, which is spin‐forbidden for N₂(X¹∑) + NO(X²Π) production, has been studied from 960 to 1130 K in a high‐temperature photochemistry reactor. No reaction could be observed, indicating k < 1 × 10^?15 cm³ molecule^?1 s^?1. It is concluded that there is no significant contribution from the spin‐allowed exothermic path leading to N₂(X¹∑) + NO(a⁴Π). © 2001 John Wiley & Sons, Inc. Int J Chem Kinet 33: 387–389, 2001     

Copper(II) complexes of 2-formyl-, 2-acetyl- and 2-benzoyl-pyridine N(4)-phenyl-, N(4)-o-methoxyphenyl-, N(4)-p-methoxy-phenyl- and N(4)-p-nitrophenylthiosemicarbazones

Summary Cu^II complexes of 2-formyl-, 2-acetyl- and 2-benzoylpyridine N(4)-phenyl-, N(4)-o-methoxyphenyl-, N(4)-p-methoxyphenyl- and N(4)-p-nitrophenyltniosemicarbazones, coordinated either as neutral or monoanionic ligands, have been prepared and characterized. I.r., electronic and e.p.r. spectra of the complexes, as well as ¹H-and ¹³C-n.m.r. spectra of the thiosemicarbazones, have been obtained. Both the thiosemicarbazones and their complexes show either modest or no growth inhibitory activity against Paecilomyces variotii. However, some of these thiosemicarbazones possess significant activity against a number of tumour cell strains.     

Metal complexes of 2-acetylpyridine N(4)-dihexyl- and N(4)-dicyclohexylthiosemicarbazones

Summary 2-Acetylpyridine N(4)-dihexyl- and N(4)-dicyclohexylthiosemicarbazone, HAc4DHex and HAc4DCHex, respectively, and Fe^III, Co^II, Co^III, Ni^II, Cu^II and Zn^II complexes have been prepared and characterized by molar conductivities, magnetic susceptibilities and spectroscopic techniques. For many of the complexes, loss of the N(2)H hydrogen occurs, and the ligands coordinate to the metal centres as NNS monoanionic, tridentate ligands, e.g., [M(NNS)X] (M = Co^II, Ni^II, Cu^II, NNS = Ac4DHex or Ac4DCHex and X = Cl or Br), [Fe(NNS)₂]ClO₄, [Co(NNS)₂]BF₄, [Cu(NNS)NO₃] and [Zn(NNS)OAc]. Zn^II ion is also chelated by neutral ligands in [Zn(HNNS)X₂] (X = Cl, Br). In addition, [Ni(Ac4DHex)-(HAc4DHex)]X (X = BF₄, ClO₄) and [Ni(HAc4DCHex)₂]-(BF₄)₂ are reported where the neutral thiosemicarbazone is coordinated via the pyridyl nitrogen, azomethine nitrogen and thione sulfur. Crystal structure determinations of HAc4DCHex and [Cu(Ac4DHex)Br] show the former to contain the bifurcated hydrogen bonded form and the latter to be planar with no significant interaction between neighbouring centres.     

(4‐Aminopyridine‐κN1)(phthalocyaninato‐κ4N)zinc(II) tetrahydrofuran disolvate

The title compound, [Zn(C₃₂H₁₆N₈)(C₅H₆N₂)]·2C₄H₈O, consists of one (phthalocyaninato)zinc (ZnPc) unit, a coordinated 4‐aminopyridine (4‐ap) molecule and two tetrahydrofuran (THF) solvent molecules. The central Zn atom is (4+1)‐coordinated by four isoindole N atoms of the Pc core and by the pyridine N atom of 4‐aminopyridine. The Zn atom is displaced by 0.4464 (8) Å from the isoindole N₄ plane towards the pyridine N atom. The crystal structure is stabilized by intermolecular amine–phthalocyaninate N—H...N hydrogen bonds and π–π interactions between the aggregated Pc rings, which form molecular layers, and by weak van der Waals interactions between the layers. As well as hindering the aggregation of ZnPc molecules by occupying an axial position, the amino group will add new interactions which will favor applications of ZnPc, for example, as a sensitizer of photodynamic therapy.     

Nitrido-Azido-Komplexe des Molybdän(VI): Synthese und Kristallstruktur von [MoN(N3)2(terpy)]+ [MoN(N3)4]−·MoN(N3)3 (terpy)

Nitrido-Azido-Complexes of Molybdenum(VI). Synthesis and Crystal Structure of [MoN(N₃)₂(terpy)]⁺[MoN(N₃)₄] ^? · MoN(N₃)₃(terpy) (CH₃)₃SiN₃ reacts with Mo(CO)₃(terpy) in CH₃CN yielding red crystals of [MoN(N₃)₂(terpy)]⁺[MoN(N₃)₄] ^?· MoN(N₃)₃(terpy) (space group P1 , a = 1039.3 pm, b = 1384.6 pm, c = 1685.4 pm, α = 112.4°, β = 108.1°, γ = 88.3°, Z = 2, R = 0.035 for 4376 independent reflections). The structure consists of three different mononuclear complexes. In the neutral complex MoN(N₃)₃(terpy) Mo exhibits the coordination number 7 in form of a distorted pentagonal bipyramid, with the terpyridine ligand and two azido groups in the equatorial plane. The axial positions are occupied by the nitrido ligand and another azido group. The triply bonded nitrido nitrogen atom (Mo1? N1 = 165.6 pm) causes a strong trans effect resulting in a long distance of 245.7 pm to N_α of the trans bonded azido group. The cationic complex [MoN(N₃)₂(terpy)]⁺ derives from MoN(N₃)₃-(terpy) by abstraction of the trans bonded azido group. For the molybdenum atom remains the coordination number 6 in form of the rarely found pentagonal pyramid. In the anion [MoN(N₃)₄]^? the molybdenum atom exhibits the coordination number 5 in form of a tetragonal pyramid with the nitrido ligand in the apex. The square basic plane is formed by the N_α atoms of the azido groups.     

Crystal Structures of (PPh3)2Pd(N3)2, (AsPh3)2Pd(N3)2, (2‐Chloropyridine)2Pd(N3)2, [(AsPh4)2][Pd2(N3)4Cl2], [(PNP)2][Pd(N3)4], [(AsPh4)2][Pt(N3)4] · 2 H2O,and [(AsPh4)2][Pt(N3)6]

The crystal structures of the monomeric palladium(II) azide complexes of the type L₂Pd(N₃)₂ (L = PPh₃ ( 1 ), AsPh₃ ( 2 ), and 2‐chloropyridine ( 3 )), the dimeric [(AsPh₄)₂][Pd₂(N₃)₄Cl₂] ( 4 ), the homoleptic azido palladate [(PNP)₂][Pd(N₃)₄] ( 5 ) and the homoleptic azido platinates [(AsPh₄)₂][Pt(N₃)₄] · 2 H₂O ( 6 ) and [(AsPh₄)₂][Pt(N₃)₆] ( 7 ) were determined by X‐ray diffraction at single crystals. 1 and 2 are isotypic and crystallize in the triclinic space group P1. 1 , 2 and 3 show terminal azide ligands in trans position. In 4 the [Pd₂(N₃)₄Cl₂]^2– anions show end‐on bridging azide groups as well as terminal chlorine atoms and azide ligands. The anions in 5 and 6 show azide ligands in equal positions with almost local C_4h symmetry at the platinum and palladium atom respectively. The metal atoms show a planar surrounding. The [Pt(N₃)₆]^2– anions in 7 are centrosymmetric (idealized S₆ symmetry) with an octahedral surrounding of six nitrogen atoms at the platinum centers.     

Copper(II) complexes of 2-formyl-,2-acetyl- and 2-benzoylpyridine N(4)-o-, N(4)-m-, N(4)-p-chlorophenylthiosemicarbazones

Summary Cu^II complexes of 2-formyl, 2-acetyl- and 2-benzoylpyridine N(4)-o-, N(4)-m- and N(4)-p-chlorophenylthiosemicarbazones, coordinated either as a neutral or monoanionic ligand, have been prepared and characterized. I.r., electronic and e.s.r. spectra of the complexes, as well as ¹H- and ¹³C-n.m.r. spectra of the thiosemicarbazones, have been obtained. Both the thiosemicarbazones and their Cu^II complexes show either modest or no growth inhibitory activity against Paecilomyces variotii. Some of the thiosemicarbazones demonstrated significant activity against tumour cell strains.     

Die Kristallstrukturen der Azido‐Platinate (AsPh4)2[Pt(N3)4] und (AsPh4)2[Pt(N3)6]

Crystal Structures of the Azido Platinates (AsPh₄)₂[Pt(N₃)₄] and (AsPh₄)₂[Pt(N₃)₆] The crystal structures of the two homoleptic azido platinates (AsPh₄)₂[Pt(N₃)₄] ( 1 ) and (AsPh₄)₂[Pt(N₃)₆] ( 2 ) were determined by X‐ray diffraction at single crystals. In 1 the [Pt(N₃)₄]^2– ions are without crystallographic site‐symmetry, and the platinum atoms show a planar surrounding. The [Pt(N₃)₆]^2– ions in 2 are centrosymmetric (C_i) with an octahedral surrounding at the platinum atoms. While 1 is highly explosive, 2 is of significantly greater stability. This behaviour is explained by the packing conditions. 1 : Space group P2₁/n, Z = 6, lattice dimensions at –80 °C: a = 1045.3(1), b = 1620.2(1), c = 4041.0(3) pm; β = 96.70(1)°; R₁ = 0.0654. 2 : Space group P1, Z = 1, lattice dimenstions at –80 °C: a = 1027.6(1), b = 1049.1(2), c = 1249.9(3) pm; α = 88.27(1)°, β = 74.13(1)°, γ = 67.90(1)°; R₁ = 0.0417.     

Tetraazidodiammincobaltate(III): Cis-[Co(N3)4(NH3)2]− und [Co(N3)4en]−

Tetra-azidodiamminecobaltates(III): cis-[Co(N₃)₄(NH₃)₂]^? and [Co(N₃)₄en]^? The preparation and the properties of complexes containing the anions cis-[Co(N₃)₄(NH₃)₂]^? and [Co(N₃)₄en]^? are described. The compounds [Co(NH₃)₆][Co(N₃)₄(NH₃)₂ · H₂O], [Co(N₃)₂(NH₃)₄][Co(N₃)₄(NH₃)₂], [As(C₆H₅)₄][Co(N₃)₄en], cis- and trans-[Co(N₃)₂en₂][Co(N₃)₄en] have been isolated.     

Copper(II) complexes of 4-formylantipyrine N(4)-substitutedthiosemicarbazones

Copper(II) complexes between three 4-formylantipyrine N(4)-substituted thiosemicarbazones and four copper(II) salts have been prepared and characterized. I.r., electronic and e.s.r. spectra of the complexes, as well as i.r., electronic and 1H and 13C-n.m.r. spectra of the thiosemicarbazones, have been obtained. Both mononuclear and binuclear complexes have been formed with bridging ligands for the latter, being either chloro or acetato. The stoichiometries of the complexes are dependent on both the steric requirements of the thiosemicarbazone ligands and the electronic effects of their N(4)-substituents.     

Über das metallreiche Lanthannitridoboratnitrid La5(B2N4)N2

On the Metal‐rich Lanthanum Nitridoborate Nitride La₅(B₂N₄)N₂ La₅(B₂N₄)N₂ was synthesized by solid state reactions in fused tantalum containers from Li₃(BN₂), LaCl₃, Li₃N and La at 950 °C. The crystal structure refinement on a needle‐shaped single‐crystal yielded the monoclinic space group C2/m, the lattice parameters a = 1259.5(2), b = 368.53(4), c = 909.4(2) pm, β = 106.03(2)°, and R values of R1 = 0.041, wR2 = 0.066 for all independent reflections. The new compound La₅(B₂N₄)N₂ introduces the member with x = 2 to the formula type RE_3+x(B₂N₄)N_x (RE = rare earth, x = 0, 1). The structure contains the nitridoborate ion B₂N₄^8– that is isoelectronic with the oxalate ion and N^3–. Corresponding with (La³⁺)₅(B₂N₄)^8–(N^3–)₂(e^–) one additional electron is present.