Helical chirality of pyrrolo[1,2-a][1,10]phenanthroline derivatives

The objective of the study was to confirm by X-ray analysis the phenomenon of helical chirality inferred from solution ¹H-NMR data for a series of derivatives based on the novel pyrrolo[1,2-a][1,10]phenanthroline system. The syntheses of the title compounds and their ¹H-NMR data are presented. Crystals of the representative compound ethyl, 1-(4-phenylbenzoyl)-pyrrolo[1,2-a][1,10]phenanthroline-3-carboxylate, with molecular formula C₃₁H₂₂N₂O₃, were found to crystallize in the triclinic system, space group P 1 with a = 7.8541(1), b = 11.2605(2), c = 13.4093(3) Å, = 92.244(1), = 90.292(1), = 106.475(1) and Z = 2. The X-ray analysis revealed the predicted helicity of the phenanthroline system as well as its origin, namely the proximity of the pyridine N atom and the carbonyl C atom of the phenylbenzoyl residue, with non-bonded distance N s C of only 2.465(2) Å. A secondary, but significant distortion, involving displacement of the carbonyl C atom by more than 0.5 Å from the pyrrole ring, was evident. The crystal structure is maintained by C–H s O hydrogen bonds and – interactions.     

Crystal structures of (I) 2-(9,9-dipropylfluorene-2-yl)-9,9- dipropylfluorene and (II) 2-(1,1-dimethylpropyl)-7- {4-[(1,1-dimethylpropyl)-9,9-diethylfluoren-2-yl]phenyl}-9,9-diethylfluorene and (III) 2-(4-ethylphenyl) -7-[7-(ethylphenyl)-9,9-dipropylfluoren-2-yl]-9,9-dipropylfluorene

The crystal structures of the three fluorene related molecules, (I) 2-(9,9-dipropylfluorene-2-yl)-9,9-dipropylfluorene, [Exalite 384, C₃₈H₄₂], (II) 2-(1,1-dimethylpropyl)-7-{4-[(1,1-dimethylpropyl)-9,9-diethylfluoren-2-yl] phenyl}-9,9-diethylfluorene, [Exalite 404, C₅₀ H₅₈], and (III) 2-(4-ethylphenyl)-7-[7-(ethylphenyl)-9,9-dipropylfluoren-2-yl]-9,9-dipropylfluorene, [Exalite 416, C₅₄H₅₈], have been determined. Structural details reveal a novel new bonding arrangement at the C2 atoms of symmetry-related fluorene moieties in all three molecules producing a linear type array with an inversion center connecting adjacent asymmetric units within each molecule. Exalite 384 is monoclinic, space group P2₁/c with a = 9.002(2) Å, b = 16.275(4) Å, c = 10.525(1) Å, = 103.05(1), and V = 1502.1(5) ų with Z = 4, for d _calc = 1.103 g/cm³. Exalite 404 is triclinic, space group P1 with a = 10.383(1) Å, b = 13.404(2) Å, c = 7.7007(9) Å, = 105.296(9), = 104.23(1), = 73.707(9), and V = 974.9(2) ų with Z = 2, for d _calc = 1.141. Exalite 416 is monoclinic, space group P2₁/c with a = 15.99(10) Å, b = 11.178(8) Å, c = 23.766(4) Å, = 104.21(4), and V = 4117(4) ų with Z = 4, for d _calc = 1.141 g/cm³.     

Crystal structure of 5α-bromo-8β,9α-dimethyl-hydrindane-1,4-dione

The molecular structure of 5-bromo-8,9-dimethylhydrindane-1,4-dione (C₁₁H₁₅BrO₂) has been confirmed using three-dimensional X-ray data collected by means of a Picker FACS-1 four-circle diffractometer. The compound crystallized in the space groupC2/c with unit cell constantsa = 26.56(5),b = 6.68(1),c = 12.32(2) Å and = 90.6(1) °; the density was 1.55 g cm^–3 andZ = 8. Least-squares refinement of the positional and anistropic thermal parameters gave a finalR ₁ value of 0.083 for 793 significant reflections.     

Crystal and molecular structure of 5-bromo-pentacyclo[4.3.0.02,5.03,8.04,7]nonane-4-carboxylic acid,C10H9BrO2

The structure of the title compound, C₁₀H₉BrO₂, was determined by X-rays.M _r =241.08, triclinic, space groupP¯1,a=5.800(1),b=6.441(1),c=12.030(1) Å,=92.90(1)°,=95.65(2)°, =95.69(2)°,V _c =444.2 ų,Z=2,D _x =1.80 Mg m^–3, MoK radiation (graphite crystal monochromator, =0.71069 Å),(MoK)=48.58 cm^–1,T=290 K. Final conventionalR-factor=0.037,R _w =0.044 for 1863 observed reflections and 145 variables. The structure was solved usingMultan andDirdif. The results show that the 5-bromo substituent has a marked effect on the geometry of the homocubane skeleton. Its presence prevents a complete release of geometrical strain and induces a shortening of the bond distances to the apex carbon atom.     

Synthesis and structure of 4-R,5-R-[5-(hydroxy-diphenyl-methyl)-2, 2-dimethyl-[1,3]dioxolan-4-yl]-phenyl-methanone, a chiral ligand building block

A triphenyl analog of taddol, 4-R,5-R-[5-(hydroxy-diphenyl-methyl)-2,2-dimethyl-[1,3]dioxolan-4-yl]-phenyl-methanone, has been synthesized and structurally characterized. This molecule could act as a chiral ligand building block in the creation of tuned taddol analogs. Structural analysis of the title compound reveals that the hydroxyl group is involved in an intramolecular hydrogen bond and does not take part in any intermolecular interaction. Crystal packing is influenced by C–H O hydrogen bonding and phenyl phenyl interactions. Crystal data: Triclinic, P1 (No. 1), a = 5.9343(4) Å, b = 8.2367(17) Å, c = 10.987(2) Å, = 88.290(6), = 75.442(4), = 80.655(6), V = 512.86(15) ų, Z = 1, D _calc = 1.258 mg/m³. Final residual values were R ₁ = 0.0407 for 3022 observed data (I > 2s(I) ) and wR ₂ = 0.0941 for all 3524 unique data.     

The pseudoguaianolide isoconfertiflorin

The sesquiterpene lactone isoconfertiflorin, C₁₇H₂₂O₅, 1, crystallizes in trigonal space group P3₁ with a = 10.4498(5), c = 12.7516(8) Å, V = 1205.9(2) ų, and Z = 3. It differs from confertiflorin in having an endocyclic C=C bond in the lactone ring, which carries an exocyclic methyl group. The seven-membered ring adopts an approximate twist-chair conformation with C10 lying in the local two-fold axis, and asymmetry parameter C₂ = 5.8°. The cyclopentanone ring has the half-chair conformation with C4 on the local two-fold axis, and C₂ = 0.9°. The lactone ring is almost planar with maximum deviation 0.014(2) Å. Both methyl groups on the 7-membered ring are –oriented. The acetyl group at C8 has an orientation.     

Structural analysis of tris(tetra-n-butylammonium) hexakisisothiocyanatoyttrate(III)

The structural analysis of [(n-C₄H₉)₄N]₃[Y(NCS)₆] (I) using single-crystal diffraction data and full-matrix least squares refinement has been carried out. The hexaisothiocyanate complex crystallizes in the centrosymmetric triclinic space group P (No. 2) with unit cell constants of a = 12.431(1), b = 12.866(1), c = 22.750(2) Å, = 90.78(1), = 92.05(1), = 96.67(1)°, and Z = 2. The molecular unit consists of three separate cationic tetra-n-butylammonium groups and an independent hexakisisothiocyanatoyttrate anionic group in which the six thiocyanate ligands are octahedrally coordinated through the N atom to the Y central ion. Selected bond distances and angles are presented as well as the synthesis and peripheral studies of (I).     

Synthesis and crystal structures of quadruply carboxylate-bridged dimeric lanthanide(III) complexes of betaine

Three dimeric lanthanide(III) complexes, [Eu₂(bet)₈(H₂O)₄](CIO₄)₆ (1), [Tb₂(bet)₈(H₂O)₄](ClO₄)₆ (2), and [Eu₂(bet)₄(H₂O)₈] Cl₆·6H₂O (3) (bet = Me₃N⁺CH₂COO^–, trimethyl-aminoacetate), have been prepared and structurally characterized by X-ray crystallography. Complex 1 crystallizes in the monoclinic space group P2₁/c, with a = 11.7807(8), b = 27.757(5), c = 11.7980(8) Å, = 99.500(4)°, V = 3805.1(8) ų, and Z = 2. Complex 2 is isomorphous to complex 1, crystallizing in the monoclinic space group P2₁/c, with a = 11.7769(14), b = 27.725(3), c = 11.795(5) Å, = 99.668(14)°, V = 3797(2) ų, and Z = 2. Complex 3 crystallizes in the orthorhombic space group Pbca, with a = 12.5664(8), b = 17.8645(9), c = 22.2573(8) Å, V = 4996.6(4) ų and Z = 4. Both complexes 1 and 2 comprise quadruply carboxylate-O,O-bridged [M₂(bet)₄]⁶⁺ dimeric cores (M = Eu, Tb), and each metal ion is further coordinated by two terminal aqua ligands and two monodentate bet carboxylates to form a distorted square-antiprismatic coordination geometry. Complex 3 also has a [Eu₂(bet)₄]⁶⁺ core, in which two bet ligands act in the ¹:¹:₂ bridging fashion, and the other two bet ligands in the less common ²:¹:₂ bridging fashion, namely bridging-chelate mode. Each europium(III) ion in complex 3 is further coordinated by four water molecules to complete a monocapped square antiprism.     

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.     

Complexation with diol host compounds. Part 3. Molecular inclusion of 4-methylcyclohexanone and 2-methylcyclohexanone by the host,trans-9,10-dihydroxy-9,10-diphenyl-9,10-dihydroanthracene

The structures of the 12 molecular complexes oftrans-9,10-dihydroxy-9,10-diphenyl-9,10-dihydroanthracene with 4-methylcyclohexanone (1) and with 2-methylcyclohexanone (2) have been determined by X-ray crystallography. The crystal data are as follows: Compound (1):P2₂/c,a=8.838(2) Å,b=8.92(1) Å,c=20.879(8)=Å,=98.67(2)°,V=1627(2) ų,Z=2 andR=0.062 for 2201 unique MoK reflections; Compound (2):P¯1,a=8.917(3) Å,b=9.900(2) Å,c=11.250(4) Å,a=68.72(2)°,=64.39(3)°, =74.86(2)°,V=828.1(5) ų,Z=1 andR=0.098 for 2563 unique reflections. Both inclusion compounds exhibit O-HO=C hydrogen bonding interactions. The thermal properties of these compounds have been characterized by DTA and TGA thermograms.     

Crystal and molecular structure of bis-(1-<Emphasis Type="Italic">tert-</Emphasis>butyl-1,2-dibenzoylhydrazine)-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>′-sulfide

The structure of the title compound bis-(1-tert-butyl-1,2-dibenzoylhydrazine)-N,N- sulfide was determined by X-ray single crystal diffraction. The crystal belongs to monoclinic, space group P2(1)/c with the following crystallographic parameters: a = 14.681(7) Å, b = 14.501(7) Å, c = 16.535(8) Å, = 90°, = 109.173(9)°, = 90°, V = 3325(3) Å ³, z = 4, Dx = 1.244 mg/m³, F(000) = 1320, T = 293(2) K, 1.47° 25.00°, the final R factor: R₁ = 0.0584, wR₂ = 0.1111. The bond distances and angles in the tert-butyl groups are different, that can interpret its ¹H NMR spectra, which are very unusual for the absorption of –CMe₃ being multiple.     

The crystal structure of a cyclodecabis[1,2,3]selenadiazole

4,5,6,10,11,12-hexahydrocyclodeca[1,2-d6,7-d]bis[1,2,3]selenadiazole, C₁₀H₁₂N₄Se₂, crystallizes in triclinic space group P witha=5.4625(3),b=7.2091(4),c=8.3122(6) , =65.313(5), =77.476(5), =77.442(5)°,V=287.35(4) ³,Z=1. The structure was refined toR=0.031 andR _w=0.030 for 2018 observed reflections. The molecule lies on an inversion center. The cyclodecadiene ring adopts an elongated chair conformation. The near-zero torsion angle of the elongated chair lies at the ring-fusion bonds, with a magnitude of 2.9(3)°. The five atoms of the selenadiazole ring exhibit maximum deviation 0.005(2) from planarity, with the adjacent carbon atoms lying respectively 0.020(2) and 0.059(2) to the same side of this plane. The torsion angles about the bonds comprising the sides of the elongated chair vary in magnitude from 61.0(2)° to 55.7(2)°. The cyclodecadiene C=C bond lengths are 1.368(2) . The selenium-carbon bond length is 1.850(2) . The Se–N distance is quite long, 1.888(2) .     

Molecular structure of P-(2,4,6-tri-tert-buthylphenyl)-phenylmethylene(phenylsulfonylimino)-σ3λ5-phosphorane

The crystal and molecular structure of P-(2,4,6-tri-tert-buthylphenyl)-phenylmethylene (phenylsulfonylimino)-³⁵-phosphorane, 2,4,6-Bu^t ₃-C₆H₂-P(=CHPh)(=N--SO₂Ph), has been determined. Crystal data: triclinic, , a = 9.472(5), b = 11.427(5), c = 13.684(5) Å, = 90.61(3), = 101.21(4), = 97.02(4)°, V = 1441.1 ų, Z = 2, D _c = 1.20 g cm^–3. The observed in 1 noticeable elongation of the P=N bond 1.563(3) Å and shortening of the P=C bond 1.617(3)Å have been discussed in terms of the electron withdrawing ability of substituents on the basis of ab initio (HF/6–31+G**) calculations of the model systems.     

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.     

Molecular and crystal structure of two nickel(II) 1,2-dithiooxalato-S,S′ complexes using 1-(Rbenzyl)pyridinium cation (R = 4′-bromo-2′-fluoro or 4′-bromo)

[BrFPy]₂[Ni(dto)₂] (1) and [BrPy]₂[Ni(dto)₂] (2) complexes have been prepared by reaction of Na₂[Ni(S₂C₂O₂)₂] and the corresponding 1-(Rbenzyl)pyridinium bromide salt (R₁ = 4-bromo-2-fluoro, R₂ = 4-bromo). The crystallographic data for 1: monoclinic P2₁/c, a = 14.2192(1) Å, b = 14.2533(4) Å, c = 15.6535(3) Å, = 96.463(1)°, V = 3152.34(11) ų, Z = 4. Two cations, [Br₁F₁Py]⁺ and [Br₂F₂Py]⁺, both adopt a conformation where both the aromatic rings are twisted to the corresponding N(1)–C(10)–C(11) or N(2)–C(22)–C(23) reference plane. Data for 2: triclinic , a = 9.4042(3) Å, b = 9.6814(4) Å, c = 10.3357(4) Å, = 80.155(1)°, = 65.245(1)°, = 64.259(1)°, V = 769.68(5) ų, Z = 1. The [Ni(dto)₂]^2– anion exhibits a quasi-planar structure in both complexes. An extensive hydrogen bond network of C–H O is clearly observed in 1 and 2, and two complexes show similar crystal packing.     

Crystal and molecular structure of: 5-(1-oxoethyl)-1-methyl-2-(5-bromo-6-methoxy-2-naphthyl)-6-oxabicyclo[3.2.1]octan-7-one and 5-(1-oxoethyl)-1-methyl-2-(5-bromo-6-methoxy-2-naphthyl)-6-oxabicyclo[3.2.1]octane

X-ray crystallographic studies of the two title compounds have shown that the molecules crystallize in the same triclinic space group, , with very similar cell dimensions. For C₂₁H₂₁BrO₄,a=12.056(5),b=13.206(5),c=7.595(3)Å, =90.38(3), =106.07(3) and =124.42(3)° and for C₂₁H₂₃BrO₃,a=12.076(6),b=13.090(5),c=7.490(3)Å, =92.65(5), =104.90(5) and =124.55(5)°. Both compounds possess the oxabicyclo[3.2.1]octane bridged ring system and differ only at the carbon to the ring oxygen where the Csp³ in the ether is replaced by Csp²=O in the lactone. Both cyclohexane rings adopt distorted chair conformations and the lactone and ether rings approximate closely to the envelope conformation. The bromine substituent at C(4) results in distortion of the naphthalene ring. Both molecules pack with the naphthalene rings parallel to each other with interplanar spacings of 3.71 Å in the ether and 3.66Å in the lactone.     

Chemical preparation and crystal structure of 6′-butoxy-2,6-diamino-3,3′azo-dipyridine monohydrate

Chemical preparation, X-ray single crystal, and calorimetric studies of C₁₄H₁₈N₆O·H₂O are described. The compound crystallizes in the triclinic space group, P with unit cell dimensions: a = 6.2640(3), b = 10.9840(4), c = 12.2220(3) Å, = 105.03(2), = 96.96(2), = 101.6(2)°, V = 712.10(5) ų, and Z = 2. The 6-butoxy-2,6-diamino-3,3-azo-dipyridine monohydrate structure is built up from organic layers parallel to the (120) plane linked via O—H···N bond.     

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–.     

Crystal and molecular structure of 7β-(1,3-dioxolan-2-yl)-3,3aβ,4,5,6,6aβ,7,8-octahydro-7α-methyl-8-oxo-1H-naptho[1,8aα-c]furan,C16H22O4

The structure of the title compound, C₁₆H₂₂O₄, was determined by X-rays atT=290 K.M _r =264.320, triclinic, space groupP¯1,a=8.4857(9),b=10.0613(5),c=10.1499(7) Å,=122.019(5)°,=107.049(8)°,=74.892(9)°,V _c =696.5 ų,Z=2,D _x =1.260 Mg m^–3. MoK radiation (graphite crystal monochromator,=0.70926 Å),(MoK)=7.03 cm^–1. Final conventionalR-factor=0.058,R _w =0.088 for 2223 unique reflections and 247 variables. The structure was solved usingMultan andDirdif. The alkylation step in the synthetic preparation of clerodane-like compounds results in an equatorial position of the dioxolan group.     

Structural characterization and excited-state properties of luminescent <Emphasis Type="Italic">Tris</Emphasis>-(μ -3-methyl-5- trifluoromethylpyrazolato)trigold(I)

Tris-(-(3-methyl-5-trifluoromethylpyrazolato)-N:N)triangulo-trigold(I), (3,5-tfmpz)₃ Au₃, has been synthesized and exhibits a planar nine-member ring containing a central gold triangle with an average intramolecular Au–Au distance of 3.3455(8) Å. The complex crystallizes in the monoclinic space group Cc with a = 12.998(2) Å, b = 22.910 (3) Å, c = 7.217(1) Å, and = 104.781(1). The solid-state structure consists of sheets of (3,5-tfmpz)₃Au₃ units stacked in an offset fashion along the c axis such that one gold atom in each Au₃ unit (Au1) lies approximately over the midpoint of the Au1–Au3 edge of the triangle in the layer below it. The intermolecular Au–Au distances are between 3.880(1) and 4.023(1) Å, which are too long for there to be significant intertrimer bonding interaction suggesting that any supramolecular organization may be due to hydrogen-fluorine and fluorine-fluorine interactions between the molecules. The complex exhibits excitation-dependent emission at room temperature in the solid state. The structured higher energy emission (_em = 468, 517, and 556(sh) nm) is believed to be a ligand-centered ^* transition with a lower energy unstructured emission (_em = 658 nm) assigned to the classical Au–Au excited state transition.