The crystal structures of NaAlR4, R=methyl,ethyl, and n-propyl

The crystal structures of the title compounds have been determined from diffractometer data and refined by full-matrix least squares. NaAlMe₄ is orthorhombic,Cmcm,a=9.234(3),b=9.221(3),c=8.303(2) Å,Z=4,D _c=1.03 g cm^–3,R=0.029 for 278 data. NaAlEt₄ is monoclinic,P2₁/c (No. 14),a=13.900(2),b=13.207(2),c=14.443(1) Å,=117.43(1)°,Z=8,D _c=0.94 g cm^–3,R=0.056 for 2747 data. NaAl(n-Pr)₄ is monoclinic,C2/c,a=9.802(5),b=15.336(4),c=21.611(10) A,=98.34(4)°,Z=8,D _c=0.92 g cm^–3,R=0.072 for 899 data. Coordination of Al is essentially tetrahedral in all structures, and closest contacts to Na⁺ involve-carbon atoms of alkyl groups.     

Crystal and molecular structures of 5,7-dimethyl-1,8-naphthyridine-2-ol (=LH) and of its mercury (II) complex HgL2 and synthesis of some lanthanide/HgL2 heterometallic complexes

The crystal structures of the title compounds have been determined by single crystal diffraction methods. Crystals of 5,7-dimethyl-1,8-naphthyridine-2-ol (1) are monoclinic, space groupP2₁/n witha=7.336(2),b=8.989(2),c=13.125(3)Å,=95.72(3)°,V=861.2(4)ų,Z=4,D _c =1.34 g cm^–3, finalR=0.052. The molecules are linked in pairs by two N-HO hydrogen bonds, and these dimers are stacked in a discontinuous, stepped fashion. Crystals of HgL₂ (2) are monoclinic space groupP2₁,/c witha=4.044(2),b=12.147(2),c=18.093(5)Å,=93.32(2)°,V=887.3(4)ų,Z=2,D _c =2.05 g cm^–3, finalR=0.051. In2 the mercury binds to N(1) to form a linear N-Hg-N coordination geometry, and the HgL₂ molecules form a continuous stacked structure. The syntheses of the compounds ML₄(NO₃)₃·H₂O (M=Nd, Gd, and Er), PrHg₂L₄(NO₃)₃, andM ₂Hg₃L₆(NO₃)₆ (M=Gd, Er) are also reported.     

Crystal and molecular structures of the 4-(1H)-pyridone (=L) lanthanide complexes {[GdL(NO3)3(H2O)]·CH3OH}2 and [DyL4(NO3)2](NO3) and of L2HNO3

The crystal structures of the title compounds have been determined by single crystal diffraction methods. Crystals of the dysprosium compound are monoclinic, space groupP2₁/c witha=14.133(4),b=13.438(5),c=14.401 (4)Å,=103.98(2)°,V=2654(1)ų,Z=4,D _c =1.82 g cm^–3, finalR=0.035. The Dy atom is eight-coordinate with a distorted dodecahedral coordination geometry involving two bidentate nitrate groups and four pyridone oxygen atoms. An erbium complex with analogous stoichiometry was also prepared but not structurally characterized. Crystals of the Gd compound are monoclinic, space groupP2₁/n, witha=11.226(2),b=9.075(2),c=16.737(3)Å,=93.88(3)°,V=1701(1)ų,Z=2,D _c =1.91 g cm^–3, finalR=0.042. Each Gd atom is bonded to one pyridone oxygen atom, a water molecule and three bidentate nitrate groups. An oxygen atom of one of the bidentate nitrates additionally serves to bridge pairs of Gd atoms so as to form a dinuclear complex in which each Gd atom is nine-coordinate with a tricapped trigonal prismatic geometry. Crystals of L₂HNO₃ are monoclinic, space groupI2/a witha=12.479(4),b=6.535(2),c=14.297(6)Å,=96.07(3)°,V=1159(1)ų,Z=4,D _c =1.45 g cm^–3, finalR=0.057. The pyridones are linked in pairs by very short (2.44 Å) symmetrical OHO hydrogen bonds. Each pair is further linked via a nitrate ion by means of N-HO(nitrate)H-N hydrogen bonds, so as to form an extended chevron-like pyridone-pyridone-nitrate-pyridone-pyridone array. Adjacent chains are linked via weak C-HO(NO₃) interactions.     

Synthesis and structural characterization of 2,6-bis-(N-methylenemorpholino)-4-methylphenol (MMP) and 2,6-bis-(N-methylenemorpholino)-4-bromophenol (MBrP)

MMP: C₁₇H₂₆N₂O₃,M _r =306.40, monoclinic, space groupP2₁/c,a=10.927(2),b=10.777(2),c=14.197(2) , =94.04(2)°,V=1667.7(5) ³,D _cal=1.22 Mgm^–3,Z=4,F(000)=664, =5.93 cm^–1,T=293K. FinalR=0.049 andwR=0.063 for 2724 observed reflections. MBrP; C₁₆H₂₃N₂O₃Br,M _r =371.27, monoclinic, space groupP2₁/c,a=10.955(1),b=10.785(1),c=14.213(1) , =94.54(2)°,V=1674.0(4) ³,D _cal=1.48 Mgm^–3,Z=4,F(000)=768, =32.35 cm^–1,T=293K. FinalR=0.055 andwR=0.069 for 2886 observed reflections. MMP and MBrP are isostructural and in both the molecules the morpholino rings assume a chair conformation.DCB Contribution No. 824.     

Crystal structures of (η5-C5H4COMe)M(CO)3Me (M=Mo,W)

The crystal structures of ( ⁵-C₅H₄COMe)M(CO)₃Me (M=Mo,W) have been determined. They are not isostructural. M=Mo isP2₁/c,a=10.205(6),b=14.192(8),c=8.135(6) Å,=93.43(4)° andD(calc)=1.71 g cm^–3 forZ=4. M=WisP2₁/c,a=12.580(7),b=6.830(5),c=13.750(7) Å,=93.72(4)° andD(calc)=2.20 g cm^–3 forZ=4. Both have a four-legged piano stool geometry with the substituted carbon making the closest M-C( ⁵) approach. The methyl group in the M=W derivative is disordered between twotrans-ligand positions. The average bonding parameters for the more accurately determined Mo analog are: Mo-C()⁵)=2.34(3) Å, Mo-CO=1.98(2) Å, Mo-Me=2.304(4) Å.     

Crystal structures of 4-amino-1,2,4-triazolidine-3,5-dione (urazine) (C2H4N4O2) and dichlorobis (4-amino-1,2,4-triazolidine-3,5-dione-N,O) copper (II) (C4H8Cl2CuN8O4)

Crystal structure analyses of urazine and of its adduct with CuCl₂ show that this ligand can exchange interactions of stacking that cannot be defined as simple - interactions. The copper atoms are octahedrally coordinated by two oxygen atoms and two aminic nitrogen from chelating uraxines and two chlorine atoms. The crystals of urazine are monoclinicP2₁ c:a=6.741(1),b=5.815(1),c=11.141(2) Å,/gb=92.13(1)°,V _c=436.4(1) ų,Z=4,R=0.0402 for 714 independent observed reflections; the crystals of [CuCl₂(urazine)₂] are triclinicP¯1:a=5.236(1),b=6.662(1),c=8.411(1) Å,=93.00(1),=104.87(1), =105.69(1)°,V _c=270.66(8) ų,Z=1,R=0.0380 for 875 independent observed reflections.     

Structural and spectral studies of N-trans-cinnamylidene-m-toluidine and N-trans-cinnamylidene-m-chloroaniline

N-trans-cinnamylidene-m-toluidine (1) C₁₆H₁₅N, and N-trans-cinnamylidene-m-chloroaniline (2) C₁₅H₁₂NCl form isomorphous crystals which are monoclinic, space group P2_l/c, with unit cell dimensionsa=5.967(2),b=13.793(3),c=15.048(5) Å, =91.97(3)° anda=5.868(2),b=13.788(4),c=15.191(4) Å, =91.87(3)°, respectively. The single-crystal X-ray structure determinations of the title compounds revealtrans structures. Ring (A) C_10–15 and ring (B) C_1–6, are practically planar in both structures with dihedral angels of 61.3(3) and 63.6(2)°, respectively.¹H nmr, u.v. and i.r. spectra are also reported.     

Structure of (chloranilato)bis(tri-n-butylphosphine)palladium(II)

(Chloranilato)bis(tri-n-butylphosphine)palladium(II), [Pd(C₆Cl₂O₄){P(C₄H₉)₃}₂] (chloranilic acid=2,5-dichloro-3,6-dihydroxy-p-benzoquinone): FW=718.02,P2₁/c,a=21.729(6),b=17.293(5),c=21.010(9) Å,=112.62(3)°,V=7287.42 ų,Z=8,D _c=1.309mg m^–3, Mo, =0.710730 Å,=0.76 mm^–1,F(000)=3008, finalR=0.087, 2594 observed reflections. Palladium is ligated by a distorted square planar P₂O₂ coordination sphere in the title compound. The two molecules per asymmetric unit differ in the arrangement of phosphine n-butyl chains, yielding two unique metal centers.     

Coordination of Schiff bases derived from pyrrole-2-carboxaldehyde and triamines to copper(II) and nickel(II) ions. Crystal structures of [Cu(C15H20N5)]NO3 and [Ni(C15H20N5)]ClO4

The Schiffbases 1,9-bis(2-pyrrolyl)-2,5,8-triazanona-1,8-diene (H₂L¹), 1,10-bis(2-pyrrolyl)-2,5,9-triazaundeca-l,9-diene (H₂L²), and 1,11-bis(2-pyrrolyl)-6-methyl-2,6,10-triazaundeca-l,10-diene (H₂L⁴) react with copper(II) nitrate or nickel(II) perchlorate in the presence of triethylamine to give new complexes [Cu(HL^1,2,4)]NO₃ and [Ni(HL^1,2,4)]ClO₄. The crystal structures of [Cu(HL²)]NO₃ and [Ni(HL²)]CIO₄ have been determined from single crystal diffractometer data and refined to finalR factors of 5.09 and 5.3%, respectively. Crystallographic data: [Cu(HL²)]NO₃: monoclinic,P2₁/c,a=10.036(2),b=14.500(2),c=13.317(2) Å,=108.14(1)°,Z=4, andd _c =11.427 Mg m^–3; [Ni(HL²)]ClO₄: monoclinic,P2₁/n,a=10.578(3),b=13.953(3),c=12.394(4) Å,=93.78(2)°,Z=4, andd _c =1.549 Mg m^–3. In both the structures the potentially pentadentate ligand (HL²)^– acts as a tetradentate one leaving one pyrrole group uncoordinated. Interesting is the metal dependent sequence of the three chelate rings. While the Ni (II) ion coordinates the (HL²)^– ligand to form a 5-5-6-membered ring system, the ring arrangement in the copper complex is of the 5-6-5 type.     

Crystal structures of two azo compounds, 2-methyl-2-(4-bromphenylazo)-1,3-indandione and 2-methyl-2-(4-ethoxyphenylazo)-1,3-indandione

In the two title compounds, the 2-methyl-1,3-dioxoindan-2-yl and 4-(brom; ethoxy) phenyl groups aretrans with respect to one another. The phenyl ring and the azo group are not coplanar in the two molecules. The five-membered rings of the two compounds adopt an envelope conformation. The crystallographic parameters are as follows: 2-Methyl-2-(4-bromphenylazo)-1,3-indandione (I): monoclinic, P2₁/a witha=8.098(2),b=14.442(2),c=12.554(1)Å, =100.55(2)^o, andD _calc=1.58 g cm^–3 forZ=4; 2-methyl-2-(4-ethoxyphenylazo)-1, 3-indandione (II): monoclinic, P2₁/a witha=8.258(2),b=14.449(1),c=13.559(2)Å, =101.19(1)^o, andD _calc=1.29 g cm^–3 forZ=4.     

Synthesis and characterization of a novel pentacyclic C16 diketone and derivatives

The syntheses and crystal structures of pentacyclo[9.4.1.0^5,14.0^7,13.0^12,15]hexadecane-3,9-dione (2), a novel C₁₆ diketone with potential inclusion ability, and the products of the reaction of2 withn-butyllithium andmeso-erythritol (i.e.,meso-1,2,3,4-butanetetrol) are described. Crystal data:2·H₂O, orthorhombic,Pmmn,a=10.7385(8),b=9.0188(6),c=6.8411(4)Å,V=662.55(7)ų, andR=0.039 (379 reflections);3 (product from reaction withn-butyllithium), triclinic,P¯1,a=8.7192(7),b=10.9351(8),c=12.1842(8)Å,=68.933(5),=75.850(6), =80.309(6)°,V=1047.0(1)ų, andR=0.081 (1811 reflections);4 (product from reaction with erythritol), triclinic,P¯1,a=7.7224(8),b=10.1976(8),c=10.7021(9)Å,=85.405(7),=85.766(8), =76.056(7)°,V=814.0(1)ų, andR=0.052 (1471 reflections).     

Crystal structure analyses of divalent metal cation complexes with neutral noncyclic ionophores. I. Mn2+ and Ca2+ complexes withN,N,N′,N′-tetrapropyl-1,2-benzodioxydiacetamide

The crystal structure of three divalent metal complexes withN,N,N,N-tetrapropyl-1,2-benzodioxydiacetamide are discussed: (1) (C₂₂H₃₆O₄N₂)₂ Mn·MnBr₄,M _r =1214.6, tetragonal, space group (No. 82),a=b=13.661(5),c=14.994(4) Å,V=2798.2 ų,Z=2,d _m =1.42,d _x =1.44gcm^–3,R=0.051 for 660 unique diffractometer data; (2) (C₂₂H₃₆O₄N₂)₂CaBr₂,M _r =985.0, monoclinic, space groupC2/c (No. 15),a=14.530(4),b=35.565(10),c=12.384(3) Å, =122.47(2)°,V=5399.2 ų,Z=4,d _x =1.21g cm^–3,R=0.056 for 2436 unique diffractometer data; (3) (C₂₂H₃₆O₄N₂) Ca(NCS)₂·solvent,M _r =548.8 + solvent, triclinic, space groupP (No. 2),a=9.341(2),b=13.203(2),c=14.237(2) Å, =75.69(1),=78.38(1), =76.66(1)°,V=1635.9 ų,Z=2,d _m =1.19,d _x (without solvent)=1.11g cm^–3,R=0.112 for 3450 unique diffractometer data. Crystals (1) and (2) are 21 complexes with the metal cations at special positions, (1) at a site of local ¯4(S ₄ ), and (2) at a site of local 2(C ₂ ) symmetry, in both cases coordinated to all eight O atoms of the two ligand molecules. Crystal (1) also contains complex anions MnBr ₄ ^2/s- . Crystal (3) is a 11 complex with a seven-coordination of the Ca²⁺, involving four O atoms of the ligand molecule, two N atoms from thiocyanate anions, and a solvent molecule.The authors thank Prof. I. J. Borowitz for the samples and Profs. J. D. Dunitz and W. Simon for valuable discussions.     

Aquadifluoro(1,10-phenanthroline)copper(II) dihydrate: X-ray crystal structure reveals strong hydrogen bonds between ligand fluoride and lattice water molecules

C₁₂H₁₄CuF₂N₂O₃,M=335.797, monoclinic, space groupP2₁/n,a=6.985(2),b=17.406(2),c=10.581(2) Å,=92.41(2)°,V=1285(1) ų,D _c =1.736 g cm^–3,Z=4,F(000)=684,(CuK)=27.0 cm^–1, =1.5418 Å,T=20°C, crystal dimensions=0.75×0.45×0.30 mm. The structure of the title compound shows it to be [Cu(phen)F₂(H₂O)]·2H₂O with pentacoordinate-square pyramidal Cu(II), short Cu-F bonds [1.890(4) and 1.891(4) Å], and short FH-O hydrogen bonds (ca. 2.68 Å) between the complex and lattice water molecule.     

Crystal and molecular structure of 2,6-dihydroxybenzoic acid

The crystal and molecular structure of 2,6-dihydroxybenzoic acid has been determined by single crystal X-ray diffraction. The crystals are monoclinic witha=5.4084(5),b=5.2240(7),c=22.986(4) Å, =94.69(3)°, space group P2₁/c,Z=4,V=647.27(16) ų,d _c =1.58Mg m^–3, The acid crystallizes as hydrogen bonded carboxylic dimers which pack to generate a herringbone motif of the type typically encountered in polycyclic aromatic compounds.     

Structures of 355-1355-1355-1tricarbonyl: structural evidence for the near-electroneutrality of the dialkylacetal substituent

The structures of the (benzene dialkylacetal)tricarbonyl chromium complexes [⁶-C₆H₅-CH(OR)₂]Cr(CO)₆ (R=Me,1; Et,2), are reported. The compounds were examined as part of a study of the conformations of the tripodal tricarbonylchromium group. For [⁶-C₆H₅-CH(OMe)₂]Cr(CO)₃,1, monoclinic,P2₁/c (# 14),a=15.235(1) Å,b=6.5304(5) Å,c=12.702 Å, =103.197(1)^o,Z=4. For [⁶-C₆H₅-CH(OEt)₂]Cr(CO)₃,2, monoclinic,P2₁/c (# 14),a=9.859(3) Å,b=10.547(3) Å,c=15.138(3) Å, =108.42(2)^o,Z=4. The data show that the molecules adopt the expected three-legged piano stool structure. The carbonyl ligands in1 adopt an eclipsed arrangement with respect to the arene ring and its substituent, while those in2 are staggered. These conformations are consistent with the notion that the acetal substituent behaves largely as an electroneutral group, or at most as a weak electronic acceptor.     

Crystal structure of phenyl bis(O-isopropylxanthato s,s′)arsenic(III)

The crystal structure of the title compound PhAs(S₂COPrⁱ)₂ has been determined by single crystal X-ray diffraction and refined by full matrix least squares analysis with anisotropic temperature factors. The crystal is monoclinic, space groupP2₁/c,a=8.889(6),b=16.174(19),c=13.506(14) Å,=102.02(7)°,V=1899.2 ų,Z=4,D _c=1.478 g cm^–3, monochromated Mo-K radiation, =0.71069 Å,=22.07 cm^–1.The geometry around the arsenic atom is square pyramidal. Each ligand is bonded to an arsenic atom through two unequal As-S bonds measuring 2.298 and 3.041 Å. The apical position is occupied by a phenyl group and a lone pair of electrons is presenttrans to the phenyl group.     

Crystal structure of bis-(rhodanine)copper(I) iodide,C6H6CuIN2O2S4

The structure of the polymeric rhodanine compound, C₆H₆CuIN₂O₂S₄, was determined by X-rays.M _r =456.8, monoclinic, space groupP2₁/c,a=4.1947(7),b=17.6999(12),c=17.1048(8) Å,=96.15(1)°,V _c =1262.6 ų,Z=4,D _c =2.40Mg m^–3, CuK radiation (graphite crystal monochromator, =1.54056 Å),(CuK)=278.9 cm^s-1,F(000)=872,T=290 K. Final conventionalR-factor=0.029, andR _w =0.044 for 2384 unique reflections and 153 variables. The structure was solved using Patterson methods andDirdif, and refined by full-matrix least-squares methods. The compound forms zigzag chains alonga. The copper atom is in trigonal pyramidal coordination, with two sulfur atoms of the thiocarbonyl group and two bridging iodine atoms. The copper-sulfur distances are 2.278(1) and 2.299(1) Å, and the copper-iodine distances are 2.657(1) and 2.814(1) Å.     

Primary to secondary sphere coordination of 18-crown-6 to lanthanide (III) nitrates: Structural analysis of [Pr(NO3)3-(18-crown-6)] and [M(NO3)3(OH2)3]·18-crown-6 (M=Y,Eu, Tb−Lu)

The direct reaction of hydrated lanthanide nitrate salts with 18-crown-6 in 31 CH₃CNCH₃OH has resulted in the isolation and structural characterization of [Pr(NO₃)₃(18-crown-6)] and [M(NO₃)₃(OH₂)₃]·18-crown-6 (M=Y, Eu, Tb–Lu). (The Eu and Yb analogs were confirmed with preliminary cell data only.) [Pr(NO₃)₃(18-crown-6)] is 12-coordinate icosahedral and crystallizes in the orthorhombic space group Pbca with (at 20°C)a=12.230(2),b=15.598(4),c=21.777(9)Å andD _calc=1.89 g cm^–3 forZ=8. The seven isostructural [Pr(NO₃)₃(18-crown-6)] complexes all contain 9-coordinate capped square antiprismatic metal centers hydrogen bonded via the bound water molecules to D_3d 18-crown-6 within the lattice to form hydrogen bonded polymeric chains. Each complex is orthorhombic Pnma with cell parameters as follows: M=Tb (20°C):a=15.242(6),b=14.253(11),c=11.070(6)Å,D _calc=1.83 g cm^–3 forZ=4; M=Dy (20°C):a=15.248(3),b=14.239(5),c=11.058(3)Å,D _calc=1.84 g cm^–3 forZ=4; M=Y (19°C):a=15.260(2),b=14.238(2),c=11.048(3) Å,D _calc=1.64 g cm^–3 for Z=4; M=Ho (20°C):a=15.226(4),b=14.208(15),c=11.028(3)Å,D _calc=1.86 g cm^–3 forZ=4; M=Er (20°C):a=15.250(3),b=14.208(7),c=11.028(3)Å,D _calc=1.87 g cm^–3 forZ=4; M=Tm (20°C):a=15.246(6),b=14.190(16),c=11.013(6) Å,D _calc=1.88 g cm^–3 forZ=4; M=Lu (21°C):a=15.244(9),b=14.158(6),c=10.980(7)Å,D _calc=1.90 g cm^–3 forZ=4.     

X-ray structure determination of a chiral synthon,essential for the synthesis of 25-2H-stigmasterol

Synthesis of sterols with varying side chains, including deuterium labeled stigmasterol and sitosterol may be performed via the Wittig-Horner coupling of a 22 aldehyde derived from stigmasterol and a suitable sulfoxide derivative of the side chain. The X-ray structure determination of this synthon have been performed since it is a crucial step in order to know the absolute configuration of the chiral carbon atoms. Crystallographic data were as follows:a=7.437(2),b=10.103(4),c=10.274(3)Å, =100.32(6)^o, =759.4 ų, space group P2₁ (No.4),Z=2,D _c=1.239 g cm^–3.     

Crystal structure and spectroscopic study of 4-(N-acetyl) cysteinyl-6,7-dimethoxy-2,2-dimethyl-3-hydroxybenzo-1H-pyran,a potential metabolite of glutathione conjugation of precocene II 3,4-epoxide

The X-ray crystal structure of the title compound has been determined. The crystals are monoclinic:P2₁/a, a=9.804(7),b=20.544(4),c=13.288(3) Å,=105.94(4)°,V _c=2561.9 ų,Z=4,D _x=1.39Mg m^–3, (MoK)=0.71069 Å. The structure was solved by direct methods and refined with 2147 reflections to a finalR value of 0.072. The 1h-pyran ring departs from ideal symmetry towards a half-chair conformation. Mass, IR, and¹H NMR spectra are also reported.