Synthesis and crystal structure of N-<Emphasis Type="Italic">tert-</Emphasis>butyl-N′-thio [O-(1-methylthioethylimino)-N″-methylcarbamic acid]-N,N′-dibenzoylhydrazine

The novel compound N-tert-butyl-N-thio[O-(1-methylthioethylimino)-N-methyl carbamic acid]- N,N-dibenzoylhydrazine has been synthesized by the reaction of N-tert-butyl-N,N-dibenzoylhydrazine with N-sulfenyl chloride of O-(1-methylthio ethylimino) -N-methylcarbamic acid. Its structure was determined by X-ray single crystal diffraction. The crystal belongs to monoclinic, space group P2₍₁₎/n with the following crystallographic parameters: a = 7.569(3) Å, b = 20.585(7) Å, c = 16.347(5) Å, = 90, = 92.606(6), = 90, V = 2544.4(14) ų, z = 4, Dx = 1.276 mg/m³, F(000) = 1032, T = 293(2) K, 2.34 25.01, the final R factor: R₁ = 0.0475, wR₂ = 0.0907. The N–N bond adopts a gauche conformation with a dihedral angle() of 98.8 for C(17)=N(1)=N(2)=C(7), whereas its parent compound N-tert-butyl-N,N-dibenzoyl hydrazine has the dihedral angle of –71.8.     

Synthesis,characterization and crystal structure of oxovanadium(IV) complex with tridentate o-van-gly and bidentate phenanthroline

A novel oxovanadium(IV) complex with tridentate schiff base and bidentate phenanthroline ligands, VO(o-van)(phen) 2H₂O[o-van-gly: o-vanillin-glycine; phen: phenanthroline], was synthesized and characterized by elemental analysis, IR and UV-vis spectra. The crystal structure was determined by X-ray single crystal diffraction analysis. The crystal of title complex (C₂₂H₂₁N₃O₇V, M_w = 490.36) belongs to triclinic, space group P-1 with the following crystallographic parameters: a = 9.247(3) Å, b = 10.125(4) Å, c = 13.100(5) Å, = 106.343(6), = 96.042(7), = 101.726(7), V = 1135.0(7) ų, Z = 2, D_c = 1.435 Mg m^–3, (MoK = 0.485 mm^–1, F(000) = 506, and final R₁ = 0.0779, wR₂ = 0.1598 for observed reflections 1606 (I > 2(I)). V(IV) is six-coordinate with three oxygen atoms and three nitrogen atoms in a distorted octahedral geometry. The complex forms a 3-D network via – stacking and hydrogen bonds.     

Crystal structure of diethoxynitrobenzene-p-tert-butylcalix [4]arene⋅2(CH3)2C=O: Evidence of intra- and intermolecular CH/π interactions forced by crystal packing

Diethoxynitrobenzene-p-tert-butylcalix[4]arene2(CH₃)₂C=O crystallized in the monoclinic system, space group P2₁/c, with cell dimensions a = 16.1437(2) Å, b = 21.0292(2) Å, c = 18.9685(3) Å and = 110.308(1)°. The asymmetric unit consists of a diethoxynitrobenzene-p-tert-butylcalix[4]arene molecule and two solvated acetone molecules. Besides the usual CH/ interaction between p-tert-butylcalix[4]arene cavity and a solvated acetone, this structure shows the intra- and intermolecular CH/ interactions among a nitrobenzene ring, ethylene bridge of the ethoxynitrobenzene side chain and a solvated acetone molecule.     

Meisenheimer complex from picric acid and diisopropylcarbodiimide

Reaction of picric acid with diisopropylcarbodiimide produces a pale yellow 1:1 adduct N-(2,4,6-trinitrophenyl)-N,N-di(isopropyl)urea (5) and a 1:2 adduct fluorescent red zwitterionic Meisenheimer complex (6) as approximately N,N,N-tri(isopropyl)-4-oxo-6-(isopropyliminio)-2-s-(2H)triazinespiro-1-2,4,6-trinitro cyclohexadienylide. Crystals of (5) are triclinic, P-1 (#2), with a = 10.444(13) Å, b = 15.47(2) Å, c = 17.74(2) Å, = 110.43(9)°, = 99.85(10)°, = 92.78(10)°, V = 2629(6) ų for Z = 6 (three molecules per asymmetric unit). Crystals of (6) are orthorhombic, Pna2₁ (#33), with a = 24.12(4), b = 9.011(19) Å, c = 10.87(2) Å, V = 2362(8) ų for Z = 4. Nitro groups in the Meisenheimer complex are twisted 2–8° from the mean formerly aryl ring plane; in (5), nitro groups are twisted out of the aryl plane by 11–62°. In the Meisenheimer complex, cationic charge is distributed over an iminium/guanidinium group; anion charge is distributed over the cyclohexadienide ring and attached nitro groups.     

Molecular structures of two conjugated ene-ynes derived from thiophene

The crystal structures of two conjugated ene-yne derivatives of thiophene are described, 2,5-di-(trimethylsilylethynyl)-3,4-dibromothiophene (1), is triclinic P witha=6.3281(4)Å,b=9.7421(6)Å,c=16.3669(9)Å; =80.516(5)°, =84.810(5)°, =74.072(5)°,Z=2,R=0.054; 2,3,4,5-tetra(trimethylsilylethynyl)thiophene (2), is monoclinic, P2₁/c with a=20.928(2)Å b=5.852(1)Å,c=23.907(2)Å; =100.245(6)°,Z=4,R=0.049. The ethynylic C atoms of both compounds lie near the thiophene plane, with deviations in the range 0.010(3)–0.455(4)Å. The phenyl groups of2 form a dihedral angle of 13.0(4)°.     

Synthesis and structure of 1,12-bis-(N-naphthalamido)-4,9-bis-(2,4,6-trimethylbenzenesulfonyl)-4,9-diaza-dodecane

1,12-Bis-(N-naphthalamido)-4,9-bis-(2,4,6-trimethylbenzenesulfonyl)-4,9-diaza-dodecane 1 was obtained from 1,8-naphthalic anhydride on successive reactions with 3-aminopropanol, 4-methylbenzenesulfonyl chloride and 1,4-bis-(2,4,6-trimethylbenzenesulfonamido)butane. The molecular structure of 1 was investigated by X-ray crystallography, NMR, and mass spectrometry. The molecule crystallizes in the triclinic space group, . The cell parameters are a = 8.1548(12), b = 15.878(3), c = 18.005(3) Å, = 97.685(10), = 93.260(15), and = 101.754(11)°. The asymmetric unit consists of the halves of two independent molecules, with Z = 2.     

A comparative study on structure and conformation of three hydroxybenzylamine ligands

Structure and conformation of three tridentate ligands are determined. All these three compounds crystallize in different space groups, the details are as follows: Bis[(3,5-dimethyl,2-hydroxy)-2-hydroxy-5-methoxy]benzylcyclohexylamine (DHBC): monoclinic I2/a (a = 17.691(1) Å, b = 9.707(1) Å, c = 24.235(2) Å, = 91.028(1)°); bis[(3,5-dimethyl,2-hydroxy)-2-hydroxy-5-bromo]benzylcyclohexylamine (DHBrBC): tetragonal P4₁2₁2 (a = b = 12.1138(1) Å, c = 28.485(1) Å) and bis[(3,5-dimethyl,2-hydroxy)-2-hydroxy-5-bromo]benzylmethylamine (DHBrBM): triclinic (a = 5.228(1), b = 12.364(1) Å, c = 13.234(1) Å, = 94.04(1)°, = 95.72(1),° = 95.90(1)°). The cyclohexane rings in DHBC and DHBrBC assume chair conformation. Both the phenyl rings are planar in all the molecules and orient at angles of 75.5(1)°, 62.2(1)°, and 53.9(2)°, respectively with each other. The bond angles around N atom show the sp³ character. Inter- and intramolecular O–HN and O–HO types of hydrogen bondings stabilize the molecules in the unit cell in addition to van der Waals forces.     

On the organoaluminum chemistry of multidentate phosphine ligands. Reaction of trimethylaluminum with bis(diphenylphosphino)methane: Synthesis and molecular structure of [Al(CH3)3]2[(C6H5)2PCH2P(C6H5)2]

Reaction of an excess of trimethylaluminum with bis(diphenylphosphino)-methane in heptane affords the crystalline complex [A1(CH₃)₃]₂[(C₆H₅)₂PCH₂P(C₆H₅)₂]. The title compound crystallizes in the triclinic space group P¯1 with unit cell parametersa=10.053(6),b=11.017(6),c=15.908(8) Å,=85.58(4),=71.80(4), =77.49(4)°,V=1634(1) ų, andD _c=1.07 g cm^–3 forZ=2. Least-squares refinement based on 2924 observed reflection with intensitiesI3I) in the range 2.00245.0° converged atR=0.050 (R _w=0.067). The Al-P distances are 2.585(2) and 2.521(2) Å, and the P-C-P angle is 121.4(2)°.     

Syntheses and structures of dihydrocalix[4]arenes bearing O-benzonitrile and O-acetonyl substituents

Three 25,27-dihydrocalix[4]arene derivatives, bearing benzonitrile and acetone groups on the oxygens, were prepared and structurally characterized. All three structures crystallize in , with cell dimensions: bis(benzonitrile)calix[4]arene·toluene, a = 11.530(2) Å, b = 12.013(2) Å, c = 14.089(4) Å, = 103.555(18)°, = 94.341(18)°, = 104.704(16)°, and V = 1815.9(7) ų; anti-bis-acetone-calix[4]arene, a = 7.5847(8) Å, b = 12.0948(17) Å, c = 15.3375(16) Å, = 78.982(10)°, = 76.932(9)°, = 73.129(10)°, and V = 1299.6(3) ų; syn-bis-acetone-calix[4]arene, a = 9.080(3) Å, b = 10.391(3) Å, c = 14.816(3) Å, = 96.998(19)°, = 100.02(2)°, = 103.93(3)°, and V = 1299.6(3) ų.     

The crystal structure of 2,2′-bis-1,3-dithiole and dimethyl dicyanofumarate CT complex

The crystal structure of 2,2-bis-1,3-dithiole dimethyl dicyanofumarate has been determined from a single-crystal X-ray study. The compound crystallizes in the monoclinic space groupP2₁/c with two complexes per unit cell of dimensionsa=11.075(2)Å,b=11.615(3)Å,c=6.623(4)Å, ==90.0°,=95.7(16)°, andV=847.6(9)ų. The observed and calculated densities are 1.56 and 1.57 g cm^–3 respectively. Full-matrix least-squares refinement using 404 reflections having 4°250° andI3(I) converged atR=0.0492 andR _w =0.0614. Structural parameters in bond lengths and bond angles do not change to any observable extent when comparing the parent molecules to the complexed state. AnOrtep view along thec-axis shows the units to be arranged in segregated parallel stacks with a distance of 3.31 Å between layers.We are indebted to the US Army Research Office, Grant DAAG-29-77-G-0231, for support of the research and to Dr. J. H. Enemark and Dr. W. Setzer for their professional advice.     

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.     

Molecular structure and absolute configuration of (−)-(1R, 2S, 6R, 7S, 2′S)-5-(2′-hydroxymethylpyrrolidin-1′-yl)-endo-tricyclo[5.2.1.02,6]deca-4,8-dien-3-one

The crystal and molecular structure of (–)-(1R, 2S, 6R, 7S, 2S)-5-(2-hydroxymethyl-pyrrolidin-1-yl)-endo-tricyclo[5.2.1.0^2,6]deca-4,8-dien-3-one is described. Knowing the absolute configuration of the prolinol moiety (S) the X-ray diffraction study established the absolute configuration of the title compound. The structure was refined to R ₁ = 0.0322 for 1237 reflections (with I > 2(I)). Crystal data: C₁₅H₁₉NO₂, monoclinic, space group P2₁, a = 6.0757(4), b = 11.3473(5), c = 9.5114(7)Å, = 104.686(6)°, V = 634.32(7)ų, and Z = 2.     

Crystal structure of 751-1751-1751-1751-2751-2751-2

The title compound crystallizes in the centrosymmetric triclinic space group (No. 2) witha=10.818(1)Å,b=10.876(1)Å,c=11.072(2)Å, =98.74(1)°, =98.83(1)°, =96.61(1)°,V=125906(3)ų andZ=2. Interatomic distances include Fe–P=2.243(2)Å, Fe–CO=1.771(6)–1.781(5)Å, Fe–C(C₅H₅)=2.074(6)–2.103(5)Å and P–F=1.511(6)–1.571(4)Å.     

A novel class of naturally occurring halogenated pyrroles, 1,1′-dimethyl-3,3′,4,4′,5,5′-hexabromo-2,2′-bipyrrole, 5,5′-dichloro-1,1′-dimethyl-3,3′,4,4′-tetrabromo-2,2′-bipyrrole, and 1,1′-dimethyl-3,3′,4,4′,5,5′-hexachloro-2,2′-bipyrrole

Crystal structure determinations of the three title hexahalogenated bipyrroles, (I) C₁₀H₆Br₆N₂, (II) C₁₀H₆Br₄Cl₂N₂, and (III) C₁₀H₆Cl₆N₂, reveal essentially planar pyrrole rings having dihedral angles of 64.7, 65.1, and 64.2° between the least-squares planes, favoring in each case a closer methyl–halogen conformation. All three complexes crystallize in the orthorhombic space group Pbcn with the following cell dimensions: (I) a = 12.654(3) Å, b = 8.853(2) Å, c = 13.753(3) Å, = = = 90°, Z = 4; (II) a = 12.438(6) Å, b = 8.753(6) Å, c = 13.696(3) Å, = = = 90°, Z = 4; (III) a = 12.088(6) Å, b = 8.566(4) Å, c = 13.486(8) Å, = = = 90°, Z = 4.     

Crystal structure refinement of nitroguanidine

The crystal and molecular structure of nitroguanidine was refined using X-ray single-crystal diffraction methods. Previous structure determinations achieved with single crystal photographic or neutron powder techniques yielded values for the C—N formal double bond-length that either equaled or exceeded the formal C—N single-bond lengths. Bond lengths were more precisely and accurately determined here than in the previous studies, but the formal double-bond length still exceeds the formal single bond lengths. Comparisons of crystal bond lengths with ab initio derived bond lengths of an isolated nitroguanidine molecule and hydrogen-bonded clusters of nitroguanidine molecules suggest that observed bond-length abnormalities are caused by intermolecular forces in the crystal. The crystal is orthorhombic, with a = 17.6390(5), b = 24.8730(7), c = 3.5903(1) Å, V = 1575.19 ų, Z = 16, and D _calc = 1.736 g cm^–3.     

Structural characterization of 2,6-bis(N-methylenepiperidino)-4-nitrophenol (MPN) and 2,6-bis-(N-methylenemorpholino)-4-nitrophenol (MMN)3

MPN: C₁₈H₂₇N₃O₃,M _r=333.43, monoclinic,P2₁/n. a=6.207(2),b=21.893(6),c=13.693(3) Å; =96.12(2)^o,V=1850.1(8) ų.,Z=4,D _cal=1.20 mg/m³,F(000)=720, (CuK)=1.5418 Å, andT=298K.R=0.042 andwR=0.049 for 1675 observed reflections. MMN: C₁₆H₂₃N₃O₅,M _r=337.38, triclinic,P,a=9.642(1) Å,b=10.123(5) Å,c=9.341(2) Å, =93.00(3)^o, =90.96(1)^o, =110.46(1)^o, V=852.5(5) ų,D _cal=1.31 mg m^–3.F(000)=360,Z=2, (CuK)=1.5418 Å,R=0.054 andwR=0.074 for 2804 observed reflections. The piperidine and morpholino rings assumechair conformation and orient each other at an angle of 44.8(1)^o (MPN) and 47.1(1)^o (MMN), respectively.Contribution No. 827 from DCB.     

Crystallographic and spectroscopic studies on ethylenediaminetetraacetic acid (edta) III. Crystal and molecular structure of α-edta and infrared studies on α- and β-edta

-Edta is monoclinic:C2/c,a= 11.812,b = 9.647,c = 12.970 Å, = 113.23 ° andZ = 4. The structure has been determined by direct methods with CuK diffractometer data, and refined by full-matrix least squares toR = 7.2% for 737 observed reflexions. The molecule exists as a zwitter ion in acis conformation, and possesses crystallographic two-fold symmetry. The nitrogen atom is protonated and takes part in hydrogen bonding. -Edta is hydrated, in this specimen, refinement indicated a value of 0.39 H₂O per molecule of edta. A short (2.47 Å) hydrogen bond links oxygen atoms in adjacent molecules. Infrared spectra are reported for both -edta and -edta; the results are discussed in terms of the crystal structures. The formulation of -edta with 0.39 mole H₂O is explained.     

X-ray crystal structure of the 1∶2 triethyleneglycol dimethyl ether (triglyme): Dichloropicric acid adduct

The anhydrous 12 triglyme:Dichloropicric acid adduct is triclinic, space group ; at 24°Ca=8.703(5),b=10.381(4), c=10.404(3) Å, =114.42(3), =99.69(5), =106.40(6)°,D _x=1.656 g cm^–3, V = 776(2)ų,Z=1. Bond lengths and angles are normal except that one C–C–O–C torsion angle in the triglyme is approximately 90° rather than the expected 60 or 180°. Each phenolic OH group hydrogen bonds with a terminal OCH₃ of the polyether. The O...O distance, 2.557(3) Å, is in fair agreement with the 2.52 Å estimated from the single observed IRv (OH) stretch at 1714 cm^–1.     

Crystal structures of two substituted key intermediates of phenothiazine derivatives

The key intermediates, in the synthesis of phenothiazines, 5-hydroxy-5-methyl 3(phenyl) 2,4-N-dimethylcarbamoyl cyclohexanone, C₁₇H₂₂O₄N₂ (I), and 5-hydroxy-5-methyl 3(2-methylphenyl) 2,4-N-dimethylcarbamoyl cyclohexanone, C₁₈H₂₄O₄N₂ (II), contain essentially substituted cyclohexanone rings in chair conformation with approximately perpendicular oriented phenyl rings. The carbamoyl groups are aligned in opposite directions to facilitate the formation of intramolecular C–HO interaction and O–HO hydrogen bonding. The molecules are linked in helical fashion by an N–HO type intermolecular hydrogen bonding framework. Crystal data: [I], orthorhombic, space group Pbca, a = 9.278(1), b = 19.094(2), c = 19.802(2) Å, V = 3508.0(6) ų, Z = 8 and d = 1.206 Mg m^–3, R = 0.074 (wR = 0.137) for 208 parameters and 1190 observed reflections with I 2 (I); [II], monoclinic, space group P2₁/n, a = 10.523(1), b = 9.005(1), c = 19.771(2) Å, = 94.96(6)°, V = 1866.5(3) ų, Z = 4 and d = 1.183 Mg m^–3, R = 0.062 (wR = 0.131) for 217 parameters and 2276 observed reflections with I 2 (I).     

Synthesis and structural studies of <Emphasis Type="Italic">tris</Emphasis>-2-chlorobenzylamine and <Emphasis Type="Italic">tris</Emphasis>-2-bromobenzylamine

The tris-2-chloro and 2-bromotribenzylamines are prepared from aqueous ammonia and 2-chlorobenzyl chloride and 2-bromobenzyl bromide, respectively, in ethanol. Recrystallization yielded colorless cubes of each product. The crystal structures are each solved in space group P , and are isostructural. The tris-2-chloro compound, 1, has a = 7.4226(5) Å, b = 9.0825(7) Å, c = 14.529(1) Å, = 78.279(1), = 82.389(1), = 84.661(1), and V = 948.41(12) ų with Z = 2, and d_calc = 1.368 Mg/m³. The tris-2-bromo analog, 2, has a = 7.6569(11) Å, b = 9.0922(13) Å, c = 14.614(2) Å, = 79.286(2), = 81.777(2), = 85.401(2), and V = 987.9(2) ų with Z = 2, and d_calc = 1.762 Mg/m³. Lithium–halogen exchange experiments conducted in tetrahydrofuran at –78C using n-butyl lithium revealed that no exchange occurred for the tris-2-chloro compound, but did occur for the tris-2-bromo analog to yield tribenzylamine upon quench and work-up.