Synthesis,structural, and spectroscopic study of rhenium(III) and rhenium(V) 4,6-dimethylpyrimidine-2-thiolate/triphenylphosphine mixed complexes: Crystal and molecular structure of ∥ReCl2(pymS)(PPh3)2∥·C3H6O and ∥ReOCl2(pymS)(PPh3)∥

4,6-dimethylpyrimidine-2(1H)-thione reacts with rhenium(V) precursorstrans-ReOX₃(PPh₃)₂ (X=Cl, Br) in acetone, to afford two classes of crystalline pyrimidinethiolate/triphenylphosphine mixed complexes:trans-Re^IIIX₂(C₆H₇N₂S)(PPh₃)₂·C₃H₆O and Re^vOX₂(C₆H₇N₂S)(PPh₃) (X=Cl, Br). The crystal structures oftrans-ReCl₂(C₆H₇N₂S)(PPh₃)₂·C₃H₆O (I) and ReOCl₂(C₆H₇N₂S)(PPh₃) (II) have been determined from single-crystal diffractometer data and refined toR factors of 0.0496 and 0.0365, respectively. (I) crystallizes in the triclinic space group P¯1 witha=16.875(4),b=13.969(7),c=9.510(2) Å;=81.78(2)°,=85.15(12)°, =107.97(8)° andZ=2. The coordination geometry around the rhenium center exhibit mutuallytrans phosphine groups and chloride ligands disposedtrans to the nitrogen and sulfur donors of the pyrimidinethiolate ligand which form a four-membered chelate ring with the metal. (II) crystallizes in the monoclinic space group P2₁/c witha=12.554(3),b=10.501(1),c=19.200(5) Å;=106.54(2)° andZ=4. The rhenium atom presents a very distorted octahedral configuration with a chlorine atomtrans to phosphine ligand in the axial position and the N,S-chelate ligand in the equatorial plane with the sulfur donor atomtrans the Re=O_oxo group. The compounds were characterized also by means of ir and nmr spectroscopic measurements; reaction pathways are discussed on the basis of structural data.     

Synthesis and crystal structure of macrocyclic nickel(II) complex bridged by chromate

A novel compound catena-(-CrO₄-O,O)[Ni(L¹)Ni(L²)] 3H₂O (1) (L¹ = 3,5,10,12-tetramethyl-1,4,8,11-tetraazacyclotetradecane and L² = 2,5,9,12-tetramethyl-1,4,8,11-tetraazacyclotetradecane) has been synthesized for the first time and structurally characterized. 1 crystallizes in the triclinic space group P with a = 9.623(1), b = 10.084(1), c = 12.723 (3) Å, = 66.74(2), = 75.20(1), = 72.02(1)°, V = 1066.2(3) ų, and Z = 2. The coordination environment around the Ni(II) ions is an axially elongated octahedron with the secondary amines of the isomeric ligands and two oxygen atoms of [CrO₄]^2–.     

Synthesis and X-ray structure of [(μ-H)Os3(CO)10(μ-η2-N=CCH=CHCH=CC2H5)]

The reaction of [Os₃(CO)₁₀(MeCN)₂] with 2-ethylpyridine at ambient temperature leads to the isolation of the cluster [(-H)Os₃(CO)₁₀(-²-N=CCH=CHCH=CC₂H₅)][3 (65% yield) which has been structurally characterized by crystallographic methods. The compound crystallizes in the triclinic space group with a = 9.334(2), b = 9.918(2), c = 11.767(1) Å, = 92.13(2), = 99.93(1), = 99.88(2)°, V = 1054.7(3) ų and Z = 2. The same edge of the osmium triangle in the cluster is bridged by both the hydrido and the heterocyclic ligands, the latter through the nitrogen and the carbon atoms of the C=N bond.     

Synthesis and crystal structure of the heterometallic square-chain polythiometalate: {[W4Ag5S16]2 · [La(DEF)2(DMF)6][La(DEF)4(DMF)4]}n

The complex (NH₄)₂ WS₄ reacts with AgNO₃ and La(NO₃)₃·6H₂O in a mixture of DEF/DMF (DEF—N,N-diethylformamide), to give a new heterometallic square-chain polythiometalate {[W₄Ag₅S₁₆]₂·[La(DEF)₂(DMF)₆]·[La(DEF)₄(DMF)₄]}_n (1). 1 crystallizes in the monoclinic space group P2/c, a = 19.5534(8), b = 16.9552(6), c = 22.3479(9) Å, = 106.053(1)°, V = 7120.1(5) ų, and Z = 2. The anion polymeric chain of 1 can be regarded as an octanuclear cyclic cluster of [W₄Ag₄S₁₆]^4– fragments linked through Ag⁺ ions. The polymeric chain is extended through the parallel edges of the square unit. The mean W—Ag distance is 2.963(16) Å. The La³⁺ cations are coordinated by different solvent molecules, the average La—O bond of these large trivalent cations is 2.47(1) Å.     

Crystal structure of a (25R)-2α,3α-epoxy-5α-spirostan-6, 23-dione hemi-ethyl acetate solvate

The compound (25R)-2,3-epoxy-5-spirostan-6,23-dione, crystallizes as a hemi-ethyl acetate solvate, having two host molecules of similar conformation per molecule of ethyl acetate, in the asymmetric unit. The O atom of the epoxy group is -oriented. The presence of the epoxy group disturbs the chair conformation in the ring A of the steroidal nucleus. Ring A has a C5,C10 half-chair conformation. The six-membered rings B, C, and F have chair conformation as expected. The D ring adopts a C14-envelope conformation and the E ring is midway between a C22,O3 half-chair and a C22-envelope conformations. The A/B, B/C, and C/D ring junctions are trans. Crystal data: C₂₇H₃₈O₅·1/2C₄H₈O₂, Monoclinic, space group P2₁, a = 7.7363(18) b = 28.769(12) c = 12.038(6) Å, = 90.88(5), V = 2679.0(10) ų, Z = 4. The packing of the molecules is assumed to be dictated by van der Waals interactions and by intermolecular C—H ··· O hydrogen bonds.     

Short H· · ·H distances in norbornene derivatives

A short H···H intramolecular interaction was reported previously for an anhydride of syn-sesquinorbornene. The synthesis and structure of a such an anhydride with an additional five-membered dithiole ring has been investigated. While hydrogen atom positions are not accurately located, the 1.62 Å separation indicates this molecule is a candidate for the shortest H···H interaction. Two cycloadducts of norbornadiene, which literature suggests might exhibit additional short interactions, are reported also; however, the isomers with minimal intramolecular interactions are the isolated products. C₂₂H₂₀O₃S₂, 3, crystallizes in P with a = 10.881(4), b = 13.712(8), C = 6.548(8) Å, = 101.32(6), = 107.49(5), = 90.49(4)°, D _calc = 1.445 g cm^–3, and Z = 2, C₂₁H₂₀O₄Cl₈, 5, in P2₁/n with a = 8.168(2), b = 13.488(4), c = 23.500(6) Å, = 94.72(2)°, D _calc = 1.597 g cm^–3, and Z = 4, C₂₁H₂₈O₄, 6, in P> with a = 12.667(2), b = 12.792(2), c = 12.540(2) Å, = 113.51(1), = 98.18(1), = 74.39(1)°, D _calc = 1.276 g cm^–3, and Z = 4.     

Crystal structure of (3,3′,4,4′-tetramethyl-1,1′-diphosphaferrocen-2-yl) carboxylic acid and its bis-[W(CO)5] complex·0.5C5H12: Conformation of 1,1′-diphosphaferrocenes

The structures of (3,3,4,4-tetramethyl-1,1-diphosphaferrocen-2-yl)carboxylic acid (1) and its bis-[W(CO)₅] pentane solvate complex (2) have been determined by X-ray analysis. The compound 1 crystallizes in the monoclinic P2₁ /n space group with Z = 4; a = 7.8404(9), b = 14.9441(16), c = 11.7730(14) Å, = 92.773(10)°, V = 1377.8(3) ų, and D_calc = 1.553 g cm^–3. The compound 2 crystallizes in the triclinic space group with two complex molecules and one pentane molecule in the unit cell. Cell parameters: a = 10.7070(2), b = 12.577(2), c = 13.239(3) Å, = 84.00(2), = 77.58(1), = 66.06(1)°, V = 1591.0(5) ų, and D_calc = 2.100 g cm^–3 .The fully eclipsed conformation of the phospholyl rings with P···P secondary bonding of 3.353(1) Å is observed in 1 and a partially eclipsed conformation is found in 2. The 10 possible conformations of 1,1-diphosphaferrocenes were described as the function of conformational parameter and observed geometry of the phospholyl rings.⁷ We suppose that the earlier conclusions concerning the destabilizing nature of 1,1-diphosphaferrocene conformations with < 100° cannot be considered as general. The mode of W – P coordination, the structural changes of 1 by W(CO)₅ coordination, the structural effect of phospholyl rings substitution by the –COOH group, and hydrogen bonds are analyzed.     

Synthesis and crystal structures of cis- and trans-1-(3′-N, N-dimethylthiocarbamoyl-4′-methoxy)-2-(3″, 4″, 5″trimethoxyphenyl) ethene

The combretastatin A-4 analogue cis-1-(3-N,N-dimethylthiocarbamoyl-4-methoxy)-2-(3,4, 5-trimethoxyphenyl) ethene (1) and its trans stereoisomer (2) were synthesized. The molecular structures of these compounds were obtained by single-crystal X-ray diffraction. Crystallization of 1 occurs in the centrosymmetric monoclinic space group C2/c (No. 15) with a = 21.468(5), b = 7.932(1), c = 23.949(3); and = 100.75(1) and Z = 8. Crystallization of 2 occurs in the centrosymmetric monoclinic space group P2₁/n (No. 14) with a = 11.7825(7), b = 11.562(1), c = 14.911(1) and = 93.294(6); and Z = 4. Details of the synthesis and the structural characterization of the title compounds are presented and discussed.     

Synthesis and crystal structure of 1D 2,3-naphtho 15-crown-5 complex [Na(N15C5)]<Subscript>2</Subscript>[Ni(i-mnt)<Subscript>2</Subscript>] containing S⋅<Emphasis Type="Italic">s</Emphasis>C and S⋅<Emphasis Type="Italic">s</Emphasis>π interactions

The reaction of 2,3-naphtho-15-crown-5 (N15C5) with Na₂[Ni(i-mnt)₂] [i-mn = 1,1-dicyanoethylene-2,2-dithiolate] affords the title complex [Na(N15C5)]₂[Ni(i-mnt)₂] (1), which is characterized by elemental analysis, FT-IR, UV-visible spectra and single crystal X-ray diffraction. 1 crystallizes in the triclinic, space group P with a = 8.291(4), b = 12.833(7), c = 12.913(6) Å, = 115.732 (7), = 105.030(7), = 90.912(8), V = 1182.2(10) ų, Z = 1 and R₁(wR₂) = 0.0422(0.1001). The single crystal X-ray analysis shows that the [Na(N15C5)]⁺ complex cations act as the bridges linking the [Ni(i-mnt)₂]^2– anions into a 1D infinite chain through Na–N interactions and SsC and Ss interactions are observed in the chain with the shortest SsC distance of 3.433 Å.     

Crystal data,optics and vibrational spectra of potassium hydrogen squarate monohydrate,KHC4O4·H2O

Single crystals of potassium hydrogen squarate monohydrate have been prepared, and the unit cell, space group and crystal optics determined:a = 8·641(1),b = 10·909(1),c = 6·563(2)Å, = 99·807(5) °,Z = 4,P2₁/c,n = 1·411(1),n = 1·674(1),n = 1·793(2), 2V(–) = 59·1(8) °,n ¦¦_t,n :a = 2·3(2) ° in obtuse . Infrared and oriented Raman spectra have been obtained, and compared with the spectra of both the acid and the [C₄O₄]^2– ion. The squarate ring is itself very nearly orthorhombic, with symmetry axes parallel to the C-C bonds. The rings lie approximately in (001), with the C-C bonds aligned witha andb.     

Preparation and crystal structures of the Ce(IV) β-diketonates, [Ce(tmhd)4] and [Ce(pmhd)4] (tmhd =2,2,6,6-tetramethylheptane-3,5-dionate and pmhd = 1-phenyl-5-methylhexane-1,3-dionate)

The cerium(IV) -diketonate compounds [Ce(-diket)₄] [where -diket = tmhd (2,2,6,6-tetramethylheptane-3,5-dionate) 1, pmhd (1-phenyl-5-methylhexane-1,3-dionate) 2] were prepared by reacting cerium(IV) ammonium nitrate [CAN; Ce(NH₄)₂(NO₃)₆] with the respective Na(-diket) compound in ethanol, and structurally characterized by single crystal X-ray diffraction. Compound 1 crystallizes in the triclinic space group with a = 12.472(4), b = 19.972(5), c = 21.436(3) Å, = 97.05(7), = 90.16(2), = 106.55(3)°, V = 5076(2) ų, Z = 4, T = 150(2) K. Compound 2 crystallizes in the monoclinic space group P2₁/n. with a = 14.817(6), b = 17.123(6), c = 19.146(3) Å, = 105.46(4)°, V = 4682(3) ų, Z = 4, T = 150(2) K. Crystals of 1 contain two independent [Ce(tmhd)₄] molecules, with four chelating tmhd ligands bonded to each metal in a distorted dodecahedral arrangement; the cerium atom in 2 is also bonded to four chelating pmhd ligands but in this case the coordination geometry is closer to square antiprism. Both complexes are air and moisture stable. Sublimation studies reveal that 1 sublimes almost quantitatively, while 2 is comparatively involatile.     

Syntheses and structures of N-phenylmaleimidetriazoles and by-products

The syntheses, properties, and structures of N-phenylmaleimidetriazole derivatives are described. Intermediates and by-products are also discussed. 1b. a = 43.997(7) Å, 5.7610(9) Å, 8.245(1) Å, = 99.339(4), C₂/c; 2a. a = 13.646(4) Å, b = 7.744(2) Å, c = 10.612(3) Å, = 91.979(6), P2₁/c. 3a. a = 22.245(1) Å, b = 22.245(1) Å, 10.010(1) Å, P42/n. 3a. a = 11.727(2) Å, b = 14.075(3) Å, c = 16.080(3) Å, = 105.859(3), = 105.331(3), = 98.187(3), P-1. 3b. a = 8.561(3) Å, b = 14.755(5) Å, c = 22.771(7) Å, = 97.006(5), P2₁/c. 3c. a = 10.500(2) Å, b = 12.189(2) Å, c = 13.040(2) Å, = 109.091(3), = 106.089(3), = 101.022(3), P-1. 8a. a = 16.389(8) Å, b = 5.749(3) Å, c = 19.316(3) Å, = 97.467(9), P2₁/n. 8b. a = 5.822(2) Å, b = 10.114(3) Å, c = 16.705(4) Å, = 84.681(5), = 82.840(5), = 75.769(4), P-1. 9b. a = 11.251(1) Å, 13.335(3) Å, 13.376(3) Å, = 102.456(4), P2₁/n. 9c. a = 15.836(3) Å, b = 8.236(2) Å, c = 5.447(3) Å, = 92.551(3), P2₁/c. 10a. a = 13.177(2) Å, b = 14.597(2) Å, c = 5.5505(8) Å, = 110.979(2), Cc. 11a. a = 14.720(2) Å, b = 13.995(2) Å, c = 38.245(6) Å, = 94.430(3), P2₁/n. 12b. a = 15.067(5) Å, b = 20.378(6) Å, c = 8.669(5) Å, = 99.16(4), = 99.32(3), = 105.23(3), P-1. 13b. a = 8.2824(6) Å, b = 10.5245(7) Å, c = 15.518(1) Å, = 92.305(1), = 100.473(1), = 100.124(1), P-1. 15a. a = 15.357(3) Å, b = 7.778(2) Å, c = 22.957(2) Å, Pbca. 16b. a = 18.0384(4) Å, b = 12.474(3) Å, c = 20.078(5) Å, Pbca.     

Synthesis and crystal structure of 4,4′-bis(4-pyridylethyl)biphenyl, noncovalently hydrogen bonded two-dimensional networks

A new pyridine containing compound, 4,4-bis(4-pyridylethyl)biphenyl 1, was synthesized and its structure was determined by X-ray crystallography. Two kinds of two-dimensional networks linked by hydrogen bonds were obtained with different crystal solvents: 1·2H₂O, monoclinic, space group P2₁/n with a = 8.3280(10), b = 5.5990(10), c = 24.054(4) Å, = 98.79(2)°, V = 1108.4(3) ų, Z = 2, Dc = 1.200 g cm^–3, R1 = 0.0558; 1·CH₃OH·2H₂O, triclinic, space group P-1 with a = 8.3310(10), b = 12.861(2), c = 13.111(2) Å, = 64.110(10), = 75.000(10), = 83.750(10)°, V = 1220.7(3) ų, Z = 2, Dc = 1.177 g cm^–3, R1 = 0.0529. It is interesting that in the hydrate the host molecule of 1 contains an essentially flat biphenyl section, while in the methanol complex the host molecule of 1 contains a substantial twist in the center of the biphenyl section. The compounds were also characterized by NMR and FTIR spectroscopies. The ¹H and ¹³C NMR assignments for 1 were carried out by 2D NMR spectral measurements in acetonitrile-d ₃.     

Crystal structure of syn-1-acetyl-9′aH-8′- methoxyspiro[indole-3,2′-oxeto[3′,2′:4,5]furo[3,2-g][1] benzopyran]2,6′-dione

The crystal structure of syn-1-acetyl-9a-hydro-8-methoxyspiro[3H-indole-3,2(2aH) oxeto[3,2-g]furo[3,2-g]benzo[ b]pyran-2,6-dione 1 was determined by X-ray diffraction analysis. It possesses P2(1)/c space group symmetry, with a = 12.391(3), b = 15.035(3), c = 9.5435(19) Å, = 93.66(3), and D _calc. = 1.517 Mg/m³ for Z = 4.     

Synthesis,structure and fluorescent property of a novel inorganic–organic zinc compound

Single crystals of a symmetrically substituted molecule, [Zn(C₃N₆H₆)(H₂O)_0.5Cl₂] (C₃N₆H₆)(H₂O)(1), have been obtained. The crystal structure of 1 shows the existence of novel layered type supramolecular structure constructed by dumbbell-shape coordinated Zn moleculeand one 2,4,6-triamine-s-triazine ligand. Crystallographic data for 1: monoclinic system, space group: C2/c, a = 12.2532(9), b = 13.8606(10), c = 18.3603(13) Å, = 99.7860(10), V = 3072.9(4) ų and Z = 8, D_c = 1.758 Mg/m³, R₁ = 0.0518. The fluorescent property of 1 has also been studied. The luminescent property of 1 attributable to both ligand ^* transitions and electronic transfer of Zn^II O transitions.     

Tris(triphenylphosphine)rhodium cyano and triphenylcyanoborate complexes: Structures and a DFT study

The structures of [Rh(CN)(PPh₃)₃](EtOH) (1), [Rh(NCBPh₃)(PPh₃)₃] (2), and [Rh(CNBPh₃)(PPh₃)₃] (3) are reported together with a density functional theory (DFT) study of the model compounds [Rh(NCBH₃)(PH₃)₃] and [Rh(CNBH₃)(PH₃)₃]. Compound 1 crystallizes in space group Pc with a = 10.4798(15) Å, b = 12.5410(18) Å, c = 19.974(3) Å and = 112.215(6)°; compound 2 crystallizes in space group with a = 12.929(2) Å, b = 14.362(2) Å, c = 17.575(3) Å and = 92.544(3)°, = 90.214(3)°, = 113.831(3)°; compound 3 crystallizes in space group with a = 12.915(2), b = 14.296(2), c = 17.664(3) Å and = 92.469(3)°, = 90.088(3)°, = 113.768(3)°. All three complexes show slight tetrahedral distortion from ideal square planar geometry (largest for 1). Differences in the reactivity and stability of 2 and 3 are interpreted according to the results of a density functional theory study.     

Crystal structure of a 1:1 molecular adduct of hexamethylenetetramine with phenylacetic acid

A 11 crystalline adduct of hexamethylenetetramine with phenylacetic acid, (CH₂)₆N₄·C₆H₅CH₂COOH, has been isolated and characterized by X-ray analysis. The compound crystallizes in space groupI¯4 (No. 82), witha=20.576(3),c=6.907(1) Å, andZ=8. The crystal structure is composed of a packing of discrete molecular aggregates corresponding to the stoichiometric formula, each being consolidated by a NH-O hydrogen bond of length 2.643(8) Å, which has no significant effect on the regular geometry of the (CH₂)₆N₄ cage system. The C-CO₂ and phenyl groups in the C₆H₅CH₂COOH moiety make a dihedral angle of 74(1)°. The structure has been refined toR=0.071 for 1350 observed (F _o >2F _o ) MoK data.     

Nonpreorganized neutral acyclic anion receptors: Structural investigations of N,N′-diphenyl-1, 3-benzenedisulfonamide and N,N′bis(4-t-butylphenyl)-1, 3-benzenedisulfonamide

The structure of N,N-diphenyl-1,3-benzenedisulfonamide (1) was determined by single crystal X-ray diffraction. It crystallizes in P2₁/n with cell dimensions: a = 11.8390(6) Å, b = 12.3950(10) Å, c = 12.1184(10) Å, = 94.388(6)°, and V = 1773.1(2) ų. Its di-t-butyl derivative, N,N-bis(4-t-butylphenyl)-1,3-benzenedisulfonamide (2), was prepared and structurally characterized as two solvated structures. Both crystallize in P with cell dimensions: 2 CF₃CH₂OH, a = 9.469(2) Å, b = 10.0039(18) Å, c = 16.385(3) Å, = 85.561(16)°, = 83.035(18)°, = 72.459(16), and V = 1467.7(5) ų; 2 ClCH₂CH₂Cl, a = 9.559(2) Å, b = 9.8125(12) Å, c = 17.100(6) Å, = 82.495(19)°, = 83.47(2)°, = 70.100(15), and V = 1491.1(6) ų. The structures exhibit hydrogen-bonding, and are evaluated in terms of preorganization for anion binding.     

A comparison of the coordination preferences of Zn, Co, and Cd(II) with the heteroscorpionate ligand (2-hydroxy-3-t-butyl-methylphenyl)bis (3,5-dimethylpyrazolyl)methane

Reaction of the Zn, Cd, or Co nitrate salts with the deprotonated ligand (2-hydroxy-3-t-butyl-methylphenyl)bis(3,5-dimethylpyrazolyl)methane (L1O^–) in methanol produced the following complexes: [(L1OH)Zn(NO₃)₂] in two isomorphs, a = 40.983(8) Å, b = 9.571(2) Å, c = 15.667(8) Å, = 90, = 106.38(1), = 90, C2/c, and a = 13.027(3) Å, b = 14.781(4) Å, c = 16.107(3) Å, = 90, = 105.30(1), = 90, P2₁/n; [(L1OH)Cd(pz)(NO₃)₂] a = 14.7476(2) Å, b = 13.5411(2) Å, c = 16.7223(2) Å, = 90, = 110.3840(10), = 90, P2₁/c; and [(L1O)Co(pz)(NO₃)] a = 11.4240(2) Å, b = 13.4498(2) Å, c = 13.8056(2) Å, = 105.2080(10), = 105.8130(10), = 112.7470(10), P . The Zn adopts a pseudotetrahedral four-coordinate geometry where the potentially tridentate ligand is actually bidentate with a protonated and uncoordinated phenoxy arm. The Co complex is pseudooctahedral six-coordinate where the phenoxy arm is deprotonated and coordinated. Finally the Cd complex is seven-coordinate but the metal is not coordinated through the phenoxy group that is again protonated.     

Caging the mercurous ion: a tetradentate tripodal nitrogen ligand enhances stability and J(1H199Hg)

The dimeric mercurous ion has been encapsulated by a pair of the tetradentate tripodal nitrogen ligands tris[(2-(6-methylpyridyl))methyl]amine (TLA). The complex [Hg₂(TLA)₂](ClO₄)₂ (1) was isolated directly from an acetonitrile solution of Hg(ClO₄)₂ 3H₂O and TLA. Complex 1 crystallizes in the triclinic space group with a = 10.537(2) Å, b = 10.751(2) Å, c = 10.907(2) Å, = 75.20(3), = 73.73(3), = 75.73(3), and Z = 1. The cation is located an inversion center. The Hg–Hg and Hg–N_amine bond distances are 2.5469(8) and 2.297(6) Å, respectively, and the average Hg–N_pyridyl bond length is 2.75(7) Å. Complex 1 was stable indefinitely in acetonitrile-d ₃ solution, permitting detection of 13 and 22 Hz heteronuclear couplings between the Hg(I) ions and the methylene protons of the ligand. Comparisons with the structures and spectroscopic properties of related mercuric and mercurous complexes are made.