Inorganic Chemistry Communications (v.3, #5)

The microhydrolysis of VO(OEt)3 on interaction with atmospheric moisture in the absence of other solvents than the compound itself leads to crystallization of a greenish black crystalline compound. The latter was identified as V6O7(OEt)12 (I), a member of the hexavanadate family, with the aid of an X-ray single crystal study (space group R-3, a=b=17.483(11), c=11.273(10) Å, α=β=90, γ=120°). The V6O19 core is highly symmetric and situated on the cross section of the crystallographic elements of symmetry. The carbon atoms of each ethoxy group are disordered between two positions arising from two different orientations possible for it.
Keywords: Crystal structures; Microhydrolysis; Vanadium complexes; Alkoxide complexes;

Optical charge transfer in the ion pair paraquat2+[Au(CN)2] by Horst Kunkely; Arnd Vogler (205-207).
In aqueous solution paraquat2+ (N,N′-dimethyl-4,4′-bipyridinium2+) and [Au(CN)2] form an ion pair (K∼90 M−1) which shows an outer-sphere [Au(CN)2] to paraquat2+ charge transfer (CT) absorption at λ max=331 nm. A band analysis yields a potential of E 0∼3.2 V for the one-electron oxidation of [Au(CN)2]. Accordingly, Au(I) is a very weak CT donor.
Keywords: Charge transfer; Cyano complexes; Gold(I) complexes; UV spectra;

Conversion of trans-[RuCl2(P-P)2] (P-P=4-membered chelate diphosphine) to cis is facilitated by treatment with AgOTf or AgBF4 in 1,2-dichloroethane, which gives mixtures of Ru–Cl–Ag heterobimetallic complexes with cis stereochemistry at Ru(II), characterised by 31P{1H} and 1H NMR spectroscopy and by FAB mass spectrometry. Treatment of these mixtures with neutral ligands (CO, CH3CN) gives cis-[RuCl(L)(P-P)2]+, whereas simultaneous treatment of trans-[RuCl2(P-P)2] with L and Ag(I) salt gives trans-[RuCl(L)(P-P)2]+.
Keywords: Diphosphine complexes; Ruthenium(II) complexes; Silver(I) complexes; Ligand substitution;

Treatment of trans-[RuCl2(P-P)2] (P-P=4-membered chelate diphosphine) with 2 equiv. of AgOTf in 1,2-dichloroethane gave labile complexes formulated cis-[Ru(OTf)2(P-P)2], which readily undergo ligand substitution reactions with neutral or anionic ligands to give cis-[Ru(L)2(P-P)2]2+ or [RuX2(P-P)2]; these have been characterised by 31P{1H} and 1H NMR spectroscopy, FAB mass spectrometry and (in some cases) X-ray crystallography.
Keywords: Diphosphine complexes; Ruthenium(II) complexes; Silver(I) complexes; Triflate complexes; Crystal structures; Ligand substitution;

The labile side-on α-carbonyl diazoalkane platinum complex (dtbpm-κ 2 P)Pt[N2C(CO2Me)2-κ 2 N,N′] (2) displays nucleophilic as well as electrophilic reactivity patterns. H2O is added stoichiometrically, forming the hydrazonido hydroxo platinum(II) complex (dtbpm-κ 2 P)Pt(OH)[NHNC(CO2Me)2] (3). Protonation of 2 with BF3·OEt2 and MeOH yields [(dtbpm-κ 2 P)Pt{NHNC(CO2Me)2-κN,κO}]+[BF4] ([4]+[BF4]). Both new complexes have been fully characterized spectroscopically and by single crystal X-ray diffraction.
Keywords: Diazoalkane coordination; Platinum complexes; Crystal structures;

Thermal condensation of trinuclear lanthanide butoxides. Molecular structure of La55-O)(μ3-OtBu)4(μ-OtBu)4(OtBu)5 by Stéphane Daniele; Liliane G. Hubert-Pfalzgraf; Peter B. Hitchcock; Michael F. Lappert (218-220).
Refluxing of Ln3(OtBu)9(tBuOH)2 (Ln=La, Nd, Yb) in toluene led to Ln5O(OtBu)13 which was characterised by X-ray diffraction in the case of lanthanum. Aggregates of higher nuclearity were obtained in similar conditions for yttrium and praseodymium.
Keywords: Lanthanides complexes; Oxo complexes; Alkoxide complexes; Yttrium; Crystal structures;

Unexpected cis preference in palladium(II) bis(diphenylphosphinoarylthiolato) complexes. Crystal structure of cis-[Pd(PPh2(C6H4-2-S))2] by Julio Real; Esther Prat; Alfonso Polo; Ángel Álvarez-Larena; J.Francesc Piniella (221-223).
The complexes [Pd(PPh2(6-R-C6H3-2-S))2] (R=H (1); R=SiMe3 (2)) have been found to exist in solution as an equilibrium cis/trans mixture, the cis complex being the major component in both cases. The use of a low polarity crystallisation solvent allows the isolation of pure cis-1. The crystals of cis-1 are monoclinic (P21/n) with a=15.559(2), b=9.5224(9), c=22.563(3) Å and β=91.91(1)°. The angles P–Pd–P of 100.57(3)° and S–Pd–S of 85.16(3)° deviate from the right angle to accommodate the bulky –PPh2 groups in the square planar geometry. The use of polar CH3CN as a crystallisation solvent allows the isolation of trans-2.
Keywords: Palladium complexes; Phosphinothiol complexes; Cis/trans isomerism; Crystal structures;

Formation of diastereomeric clusters (μ-H)Os3(CO)10{μ, η2 (S,C)-S(Allyl)CHCH2CH3} in the reaction of diallylsulfide with (μ-H)2Os3(CO)10 by Vladimir P Kirin; Vladimir A Maksakov; Alexander V Virovets; Anatoliy V Golovin (224-226).
The interaction of (μ-H)2Os3(CO)10 with diallylsulfide S(Allyl)2 results in the formation of (μ-H)Os3(CO)10{μ, η2 (S,C)-S(Allyl)CHCH2CH3} (two diastereomers, 2a,b) and Os3(CO)103(S,C,C)-S(Allyl)CH2CHCH2}. The crystal and molecular structures of 2a have been determined by X-ray analysis.
Keywords: Triosmium clusters; Allylsulfide complexes; Cluster complexes; Osmium complexes; Hydrogenation; Isomerization; Diastereomers; Crystal structures;

Reactions of bis(benzoylacetone)-1,3-diiminopropan-2-ol (abbreviated as H3L) with zinc salts in the presence of triethylamine afforded the compounds [Zn4(HL)4]·4CH3CN (1·4CH3CN) and [Zn8L4(OH)4]·2CH3CN (2·2CH3CN). Further reaction of 1 with Ni(CH3COO)2·4H2O gave the heteronuclear species [Zn2Ni2(L)2(CH3O)2(CH3OH)2] (3). The crystal structures of 1·4CH3CN, 2·2CH3CN and 3 were determined by the X-ray diffraction method.
Keywords: Crystal structures; Zinc complexes; Oligonuclear complexes; Schiff base;

Bridging bonding mode in a metal–pteridine complex. Synthesis and structural characterization of Pt2Cl4(Hmp)2 (Hmp=4-hydroxy-2-mercaptopteridine) by Tsun-Ren Chen; Ying-Yann Wu; Chi-Phi Wu; Jhy-Der Chen; Ching-Wang Huang; Tai-Chiun Keng; Ju-Chun Wang (231-233).
Reaction of PtCl2 with Hmp (Hmp=4-hydroxy-2-mercaptopteridine) afforded the unique platinum–pteridine complex Pt2Cl4(Hmp)2, in which the Hmp ligand bridges the metal centers through the pyrazine ring nitrogen atom and the sulfur atom in a neutral form. This bonding mode is in marked contrast to the usual O4,N5-chelation mode of the pteridine units found in all the other reported complexes.
Keywords: Pteridine complexes; Platinum complexes, N–H---Pt interaction; Bridging bonding mode;

Hydrothermal synthesis and characterisation of lead(II) benzene-1,3,5-tricarboxylate [Pb3BTC2]·H2O: a lead(II) carboxylate polymer by Mark R.St J Foreman; Thomas Gelbrich; Michael B Hursthouse; M.John Plater (234-238).
The coordination polymer of formula [Pb3BTC2]·H2O (BTC=1,3,5-benzenetricarboxylate) contains 2 different BTC trianions, 3 different Pb cations and 3 different carboxylate coordination modes.
Keywords: Lead complexes; Carboxylate complexes; Hydrothermal synthesis;

The reactions of the tetraaza[14]annulene Ni(II) complex (1) with chloroacyl chlorides afforded the 6,13-dichloroacylated complexes 2 and 3. By a demetallation procedure the metal free ligand of 2 was obtained. The crystal structure of the adduct 2·C6H5CH3 has been determined by the single-crystal X-ray diffraction method.
Keywords: Chloroacylation reactions; Macrocyclic complexes; Nickel(II) complexes; Crystal structures;

New ternary complexes of the types Ln(phen)L3 and Ln(bipy)L3 (phen=1,10-phenanthroline, bipy=2,2′-bipyridine; L=2-mercaptosalicylic acid; Ln=La3+, Nd3+, Sm3+, Eu3+, Gd3+, Tb3+, Ho3+, Yb3+) have been synthesized and characterized by elemental analysis, molar conductance, CD, XPS, IR, 1H NMR (DMF-d7) and electronic spectra.
Keywords: Lanthanide ternary complexes; 2-Mercaptosalicylic acid; 1,10-Phenanthroline; 2,2′-Bipyridine;

The hydrothermal reaction of CoCl2·6H2O, 3,3′-bipyridine and NaVO3 in water at 160°C for 48 h yields the three-dimensional bimetallic oxide [{Co(3,3′-bpy)2}2V4O12] (1). The structure of 1 consists of two-dimensional {Co(3,3′-bpy)2} n 2n+ networks, linked through cyclic tetranuclear {V4O12}4− clusters into a three-dimensional covalently linked assembly. Crystal data for C20H16CoN4O6V2 (1): monoclinic, P21/n, a=9.9794(6), b=16.129(1), c=13.4190(8) Å, β=93.039(1)o, V=2156.9(2) Å3, Z=4, D calc=1.753 g/cm3.
Keywords: Hydrothermal synthesis; Composite material; Bimetallic oxide; Modular synthesis; Crystal structures;

Reaction of Co(II) perchlorate hexahydrate and anhydrous Co(II) chloride with the ligand 2-(2′-pyridyl)quinoxaline (L) leads to the formation of the novel five- and six-coordinated complexes CoLCl2(DMF) (1) and [CoL2(H2O)2](ClO4)2·H2O·2CH3OH (2), correspondingly. The crystal structures of the above complexes show a trigonal bipyramidal geometry around the metal atom for complex 1 and a distorted octahedral geometry for complex 2.
Keywords: Cobalt(II) complexes; Five-coordinate complexes; Crystal structures; Quinoxaline complexes;

Hydrothermal synthesis and characterisation of lead(II) benzene-1,3,5-tricarboxylate [Pb3BTC2]·H2O: a lead(II) carboxylate polymer by Mark R.St J Foreman; Thomas Gelbrich; Michael B Hursthouse; M.John Plater (255-258).
The coordination polymer of formula [Pb3BTC2]·H2O (BTC=1,3,5-benzenetricarboxylate) contains 2 different BTC trianions, 3 different Pb cations and 3 different carboxylate coordination modes.
Keywords: Lead complexes; Carboxylate complexes; Hydrothermal synthesis;

In the presence of (nC5H11)4N+ ions, the earlier described almost planar 14-membered ring system [{(Me3Sn)2OH}2{Ni(CN)4}2]2− polymerizes via O–H⋯NC hydrogen bonds to straight, infinite ribbons, while in the presence of the slightly smaller (nC4H9)4N+ ion a faintly puckered 2-D framework had been obtained. The dimorphism of the polymeric anion seems to be controlled by weak C–H⋯NC hydrogen bonds.
Keywords: Nickel(II) complexes; Cyanide complexes; Polymeric complexes; Trimethyltinhydroxide; Tetraalkylammonium ions; Crystal structures;

Copper(II)(pyridine-2,6-dicarboxylato)(2,6-dimethanolpyridine) has been prepared and studied by the single crystal X-ray diffraction methods at 293(2) K. The compound crystallises in an orthorhombic system, space group Pbcn with a=8.196(2), b=13.124(3), c=25.612(5) Å, and Z=8 (R=0.0374 for 3175 independent reflections with I>2σ(I)). Crystal structure analysis revealed that the copper(II) atom is surrounded by two non-equivalent terdentate ligands making up an ‘all-trans’ elongated octahedral arrangement. In consequence of Jahn–Teller distortion, considerable differences are found between the ligands for the pyridine-2,6-dicarboxylate anion with the values Cu–N 1.892(3), Cu–O 2.033(2) and 2.063(2) Å, while for the 2,6-dimethanolpyridine ligand the values are 1.943(3), 2.341(3) and 2.433(2) Å. There is a relationship between the Cu–L bond distances and the five-membered metallocyclic rings (O–Cu–N). The data are compared and discussed with those found in familiar CuL2 compounds with the CuO4N2 chromophore. Based on the molecular structure, the electronic, IR and EPR spectra are discussed.
Keywords: Copper(II) complexes; Pyridine-2,6-dicarboxylate complexes; Crystal structures;

Synthesis and X-ray structures of Ni and Zn complexes of a novel oxa-azamacrocyclic system by Vladimir A. Kuksa; Solange M.S.V. Wardell; Paul Kong Thoo Lin (267-270).
The Ni (5) and Zn (6) complexes of a novel oxa-azamacrocycle (4) were obtained from the reaction of 4 and the metal chlorides in equimolar amounts. The Ni complex 5 was isolated, in the solid state, as a 1:1 metal:ligand complex while 6 was obtained as a 2:1 metal:ligand complex. The X-ray diffraction structures of 5 and 6 have been obtained. The nickel atom in 5 has an octahedral geometry and it is hexa-coordinated to the four nitrogen atoms of the macrocycle, with two oxygen atoms from the water molecules in axial positions. The nickel atom is situated on the plane formed by four nitrogen atoms and also on the plane formed by four oxygen atoms. In contrast, in 6, two oxygen donors and two chlorine atoms coordinate to each zinc atom in an approximate tetrahedral arrangement such that the zinc atoms lie outside the cavity of the macrocycle.
Keywords: Crystal structures; Oxa-azamacrocyclic complexes; Nickel complexes; Zinc complexes;