Stan A. Duraj

The Preparation and Structural Characterization of Three Structural Types of Gallium Compounds Derived from Gallium (II) Chloride

Abstract The three compounds Ga 2 Cl 4 (4-mepy) 2 ( 1 ), [GaCl 2 (4-mepy) 4 ]GaCl 4 · 1 2 (4-mepy) ( 2 ) and GaCl 2 (4-mepy) 2 (S 2 CNEt 2 ) ( 3 ) (4-mepy = 4-methylpyridine) have been prepared from reactions of gallium (II) chloride in 4-methylpyridine and characterized by single-crystal X-ray analysis. Small variations in the reaction conditions of gallium(II) chloride can produce crystals with substantially different structural properties. The three compounds described here encompass a neutral gallium(II) dimer in which each gallium is four-coordinate, an ionic compound containing both anionic and cationic gallium complex ions with different coordination numbers and a neutral six-coordinate heteroleptic dialkyldithiocarbamate species.

Room temperature dissolution of metal powders by thiourea: a novel route to transition metal isothiocyanate complexes

Abstract A new synthetic route to isothiocyanate containing materials is presented. Five isothiocyanate 4-methylpyridine (γ-picoline) compounds were prepared by refluxing metal powders (Fe, Co, Ni and Cu) with thiourea in γ-picoline. The isothiocyanate ligand is generated in situ by the isomerization of thiourea to NH4+SCN− at reflux temperatures. The complexes [Fe(NCS)2(pic)4]·pic (1), [Co(NCS)2(pic)4]·pic (2), [Ni(NCS)2(pic)4] (3), [Cu(NCS)2(pic)4]·2/3pic·1/3H2O (4), [Cu(NCS)(pic)2]x (5) (where pic=γ-picoline) were characterized by X-ray crystallography; the structural data for compounds 1–3 and 5 are presented.

Reactions of Nb2Cl6(SMe2)3 and Ta2Cl6(SMe2)3 with compounds containing NN single bonds

Abstract Ta2Cl6(SMe2)3 reacts with PhHNNHPh to afford Ta2Cl4(μ-Cl)2(μ-PhN)(PhNH2)3 (1) a compound with a TaIVTaIV single bond, with a length of 2.644(1) A. The compound crystallizes in space group Pnma with unit cell dimensions a = 22.960(8), b = 16.875(4), c = 6.367(3) A, V = 2467(1) A3, and Z = 4. The reaction of Nb2Cl6(SMe2)3 with PhHCNNCHPh, merely on mixing at room temperature produced Nb2Cl6(SMe2) [PhHC(N)PhHCNHNCHPh]·C7H8 (2) as large red crystals in ca. 50% yield. The molecule consists of two NbIV atoms, one six-coordinate and the other seven-coordinate, united by three bridging atoms (Cl, Cl, N) and a NbNb bond of length 2.681(1) A. The way in which the tridentate triazo ligand is generated is completely obscure. Crystallographic data for 2: space group P21/n with a = 11.393(3), b = 11.988(3), c = 27.233(7) A, β = 100.75(2)°, V = 3654(3) A, and Z = 4.

SYNTHESIS AND STRUCTURAL CHARACTERIZATION OF TRIS(DIMETHYLDITHIOCARBAMATE) INDIUM(III), In[S2CN(CH3)2]3

Abstract The synthesis and structure of the indium dithiocarbamate, In[S2CN(CH3)2]3·(1/2) 4-mepy (4-mepy=4-methylpyridine), is described. Indium metal was oxidized by tetramethylthiuram disulfide in 4-methylpyridine at 25°C to form a new, homoleptic indium(III) dithiocarbamate in yields exceeding 60%. In[S2CN(CH3)2]3 exists as a discrete molecule with a distorted-octahedral geometry. The compound crystallizes in the P 1 (No. 2) space group with a=9.282(1)Å, b=10.081(1)Å, c=12.502Å, α=73.91(1)°, β=70.21(1)°, γ=85.84(1)°, Z=2, V(Å)=1057.3(3), R=0.046 and Rw =0.061.

Reactivity of dithioacetic acid toward vanadocene: Crystal structure of the [(η5-C5H5)4V4(μ3-S)4] cluster

Abstract The reaction between vanadocene and dithioacetic acid gave the novel product [(η5-C5H5)4V4(μ3-S)4]. The single-crystal X-ray structure of this low-valent vanadium cluster has been determined. The crystallographic data are: monoclinic space group C2/c, a = 17.764(5), b = 8.119(2), c = 16.158(2) A, β = 116.65(2)°, V = 2083(2) A3, Z = 4. Refinement, using a data-to-parameter ratio of 12.0, converged with an unweighted discrepancy index of 4.99%. The molecule is located on a crystallographic two-fold rotation axis and consists of a central tetrahedron of vanadium atoms, each face of which is capped by a sulphur atom with vanadium-sulphur distances of 2.296(1) A. There is a cyclopentadienyl ring coordinated to each vanadium atom with vanadium-carbon distances ranging from 2.281(9) to 2.319(7) A. The vanadium-vanadium distance in [V4(μ3-S)4(η5C5H5)4] is 2.876(11) A and corresponds to a metal-metal bond order of 2/3. The cluster is paramagnetic; μeff = 2.65 μB·

Structure of 4-methylpyridinium bromide

γ-Picolinium bromide, [C 6 H 7 NH]Br, M r =174.05, monoclinic, Cm, a=8.785 (4), b=8.318 (3), c=4.920 (1) A, β=103.62 (3) o , V=349.4 (4) A 3 , Z=2, D x =1.654 g cm -3 , λ(Mo Kα)=0.71073 A, μ=57.23 cm -1 , F(000)=172, T=293 K, R=0.033 for 415 reflections with F 0 2 >3σ(F 0 2 ) and 41 vari ables. The compound consists of C 6 H 7 NH + cations and Br - anions

Structure of bis(benzenesulfonato‐O)tetrakis(pyridine‐N)copper(II)

[Cu(C 6 H 5 O 3 S) 2 (C 2 H 2 N) 4 ], M r =694.29, monoclinic, C2/c, a=15.180 (6), b=14.431 (5), c=15.269 (6) A, β=96.38 (4) o , V=3324 (2) A 3 , Z=4, D x =1.388 g cm -3 , λ(Mo Kα)=0.71073 A, μ=8.54 cm -1 , F(000)=1436, T=295 K, R=0.067, wR=0.087 for 1141 independent reflections with I≥3σ(I) and 207 variables. The [Cu(O 3 - SC 6 H 5 ) 2 (C 5 H 5 N) 4 ] complex has a distorted transoctahedral stereochemistry. The bond angles about the Cu atom are consistent with this structure type

Synthesis, structure, and characterization of Cu4S10(4-methylpyridine)4

The title compound, Cu4S10(4-methylpyridine)4 · 4-methylpyridine was prepared by three different reactions: the oxidation of copper power by sulfur and the reaction of copper (I) sulfide (or CuBr-SMe2) with cues sulfur, both in the coordinating solvent, 4-methylpyridine. Red crystals of the compound obtained by layering with hexans were subjected to single crystal X-ray diffraction. The structure was refined toR=0.026 and Rw=0.036 in a space groupP1bar (No. 2), withZ=2,a=13.983 (2) A,b=15.384( 2) Å,c=9.660 (1) Å, α = 93.87 (1)°,β=93.38 =γ=(1)°,V=2037.9 (9) Å3. The commpound has approximate S4 symmetry and consists of two pentasuffide chains linking four Cu(I) ions, each with a coordinating 2-methylpyridine. The infrared spectrum was dominated by absorption due to coodinated 4-methylpyridine with several low-energy peaks attributable to S-S stretches, which were also observed by Raman spectroscopy. A featureless electronic absorption spectrum yielded a single peak in the mar ultraviolet upon computer enhancement (λ=334 nm, ε = 10,000), most likely an intraligand transition. Cyclic voltammetry indicates that the polysulfide complex undergoes irreversible oxidation and reduction at +0.04 and −0.34 V vs. SCR respectively, at NS K in 4-methylpyridine when swept at 20 mV/sec. The electrochemical behavior was unvaried even at sweep rates as high as 100 V/sec.

4-Methylpyridinium Hydrogen Sulfide

4-Methylpyridinium hydrogen sulfide, C 6 H 7 NH + .HS - , was obtained as a by-product of the reaction between GaCl 3 and thioglycolic acid in a 4-methylpyridine solution. The compound consists of heterocyclic C 6 H 7 NH + cationic rings and HS - anions. Both the C 6 H 7 NH + cation and the HS - anion lie on crystallographic mirror planes with the N, S, two C and two H atoms positioned in the planes. The H atom of the HS - anion was not located.

A trinuclear oxoniobium(V) complex with ketone molecules as ligands, [NbOCl3(OCRR′)]3 with RC6H5 and R′=m-CH3C6H4

Abstract The title compound and a less stable homolog containing benzophenone have been prepared. X-ray crystallography shows the title compound to be a trimer in which three NbOCl 3 (OCRR′) units are joined in cyclic fashion so that there is a closed set of NbO→Nb bonds. The unusual feature of the compound is the attachment of a ketone molecule to each metal atom. The following average distances were found: NbO, 1.767(6); NbO→Nb, 2.091(7); CO→Nb, 2.167(8), NbCl, 2.330(4) A; CONb angles were in the range 158°–177°.