Infinitene: A Helically Twisted Figure-Eight [12]Circulene Topoisomer

2021 ◽  
Author(s):  
Kenichiro Itami ◽  
Maciej Krzeszewski ◽  
Hideto Ito
Keyword(s):  
Density Functional ◽  
Crystal Packing ◽  
Uv Light ◽  
Photophysical Properties ◽  
Three Dimensional ◽  
Spectroscopic Studies ◽  
Molecular Formula ◽  
Chiral Hplc ◽  
Practical Applications ◽  
Benzene Rings

New forms of molecular nanocarbons particularly looped polyarenes adopting various topologies contribute to the fundamental science and practical applications. Here we report on the synthesis of an infinity-shaped polycyclic aromatic hydrocarbon, infinitene 1 (cyclo[c.c.c.c.c.c.e.e.e.e.e.e]dodecakisbenzene) comprising consecutively fused 12-benzene rings forming an enclosed loop with a strain energy of 60.2 kcal·mol-1. Infinitene 1 represents a topoisomer of still-hypothetical [12]circulene, and its scaffold can be formally visualized as the outcome of the “stitching” of two homochiral [6]helicene subunits by their both ends. The synthetic strategy encompasses transformation of a rationally designed dithiacyclophane to cyclophadiene through the Stevens rearrangement and pyrolysis of the corresponding S,S′-bis(oxide) followed by the UV-light mediated twofold photocyclization. The structure of infinitene 1 is a unique hybrid of helicene and circulene with a molecular formula C48H24, which can be regarded as an isomer for kekulene, [6,6]carbon nanobelt ([6,6]CNB), [12]cyclacene, and tetrabenzo[8]circulene as well. Infinitene 1 is a bench-stable yellow solid with green fluorescence, and soluble to common organic solvents. The figure-eight molecular structure of 1 was unambiguously confirmed by X-ray crystallography. The scaffold of 1, reminiscent of a squeezed spring, stem from its enclosed, fully-fused architecture, is significantly compressed as manifested by a remarkably shortened distance (3.152–3.192 Å) between the centroids of two π-π stacked central benzene rings and the closest C···C distance of 2.920 Å. Combined lamellar and herringbone-like crystal packing suggested three-dimensional electronic inter-actions. Fundamental photophysical properties of infinitene 1 were thoroughly elucidated by means of UV-vis absorption and fluorescence spectroscopic studies as well as density functional theory (DFT) calculations. Its configurational stability enabled separation of the corresponding enantiomers (P,P) and (M,M) by a chiral HPLC. Circular dichroism (CD) and circularly polarized luminescence (CPL) measurements revealed that 1 has moderate |gCD| and |gCPL| values.

scholarly journals 2-[1-(1-Oxoindan-2-yl)ethyl]indan-1-one

2012 ◽  
Vol 68 (8) ◽  
pp. o2314-o2314
Author(s):  
Abdullah M. Asiri ◽  
Hassan M. Faidallah ◽  
Khalid A. Alamry ◽  
Seik Weng Ng ◽  
Edward R. T. Tiekink
Keyword(s):  
Dihedral Angle ◽  
Title Compound ◽  
Crystal Packing ◽  
Three Dimensional ◽  
Orthogonal Relationship ◽  
Compound C ◽  
First Approximation ◽  
Centroid Distance ◽  
Benzene Rings ◽  
Fused Ring

In the title compound, C20H18O2, the fused-ring systems are essentially planar (r.m.s. deviations of the nine fitted atoms = 0.009 and 0.027 Å) and exhibit an orthogonal relationship [dihedral angle = 79.83 (5)°]. To a first approximation, the ketone-O atoms are directed to opposite sides of the molecule. A three-dimensional architecture arises in the crystal packing owing to C—H...O, C—H...π and π–π interactions [between centrosymmetrically related benzene rings with centroid–centroid distance = 3.7647 (10) Å].

Structural, energetic and spectroscopic studies of new luminescent complexes based on 2-(2′-hydroxyphenyl)imidazo[1,2-a]pyridines and 1,2-phenylenediboronic acid

2018 ◽  
Vol 74 (6) ◽  
pp. 725-737 ◽  
Author(s):  
Sylwia E. Kutniewska ◽  
Katarzyna N. Jarzembska ◽  
Radosław Kamiński ◽  
Anton J. Stasyuk ◽  
Daniel T. Gryko ◽  
...  
Keyword(s):  
Molecular Orbital ◽  
Density Functional ◽  
Crystal Packing ◽  
Stokes Shift ◽  
Spectroscopic Studies ◽  
Intramolecular Proton Transfer ◽  
Pyridine Derivatives ◽  
Centrosymmetric Dimer ◽  
Energy Excitation ◽  
Methoxy Derivative

Three new blue-luminescent complexes of selected imidazo[1,2-a]pyridine derivatives and 1,2-phenylenediboronic acid have been synthesized and structurally characterized using single-crystal X-ray diffraction. Additionally, the crystal structures of two of the (N,O)-donor compounds have been evaluated for the first time. The crystal packing and molecular motifs observed in the studied crystals have been thoroughly analysed, including computational studies, and are also discussed within the context of analogous systems reported in the literature. It appears that the new compounds form different crystal networks with regard to the asymmetric unit content and packing, although some similarities can be found. In all cases a typical centrosymmetric dimer bound via boronic acid groups is formed, characterized by an interaction energy of about −80 kJ mol−1, while the 2-(2′-hydroxyphenyl)imidazo[1,2-a]pyridine complex and its methoxy derivative form solvate structures, somewhat resembling the previously studied 8-oxyquinolinate analogues. As far as the spectroscopic properties are concerned, the lowest energy excitation observed in the studied complexes is based on the highest occupied molecular orbital–lowest unoccupied molecular orbital transition, and both these molecular orbitals are centred predominantly on the (N,O)-donor species according to the results of time-dependent density functional theory. Thus, the charge transfer observed for the 8-oxyquinolinate equivalents does not occur in these cases. Consequently, the spectroscopic behaviour of the series is very much comparable with that of the parent imidazo[1,2-a]pyridine derivatives, if the excited-state intramolecular proton-transfer process does not take place, as shown by the absorption and emission spectra collected in toluene and acetone solutions. Complexation causes a reduction in the Stokes shift compared with the respective (N,O)-donor molecules.

scholarly journals Computational and Crystallographic Examination of Naphthoquinone Based Diarylethene Photochromes

Molecules ◽  
2020 ◽  
Vol 25 (11) ◽  
pp. 2630
Author(s):  
Dinesh G. Patel ◽  
Martial Boggio-Pasqua ◽  
Travis B. Mitchell ◽  
Ian M. Walton ◽  
William R. Quigley ◽  
...  
Keyword(s):  
Solid State ◽  
Density Functional ◽  
Uv Light ◽  
Ring Closure ◽  
Thermal Stabilities ◽  
Practical Applications ◽  
Photochromic Compounds ◽  
X Ray Crystallography ◽  
High Fatigue ◽  
History Of

Photochromic compounds have a lengthy history of study and a profusion of applications that stand to gain from these studies. Among the classes of photochromic compounds, diarylethenes show desirable properties including high fatigue resistance and thermal stability, thus meeting some of the most important criteria necessary to enter the realm of practical applications. Recently, photochromic diarylethenes containing quinone functionalities have demonstrated interesting optical and solid-state properties. When properly interfaced with suitable electron withdrawing groups on the aryl component, both the ring-opening and ring-closing reactions can be achieved with visible light; this is in contrast to most other diarylethenes where UV light is required for ring closure. Unfortunately, quantitative conversion from open to closed forms is not possible. In this work, we examine the relative energies of conformations of solid-state structures observed by X-ray crystallography and evaluate their thermal stabilities based on density functional theory (DFT) calculations. Time-dependent DFT (TD–DFT) is used to model the UV-vis absorption spectra of these quinone diarylethenes. We show that spectral overlap between open and closed forms is a major hindrance to full photoconversion.

scholarly journals Crystal structure of ethylN-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)carbamate

2015 ◽  
Vol 71 (4) ◽  
pp. o267-o267 ◽  
Author(s):  
Muhammad Danish ◽  
Muhammad Nawaz Tahir ◽  
Uzma Anwar ◽  
Muhammad Asam Raza
Keyword(s):  
Crystal Packing ◽  
Three Dimensional ◽  
Pyrazole Ring ◽  
Ester Group ◽  
Stacking Interactions ◽  
Compound C ◽  
Dimensional Network ◽  
Centroid Distance ◽  
Benzene Rings ◽  
Ring Motif

In the title compound, C14H17N3O3, the dihedral angle between the benzene ring and the five-membered dihydropyrazole ring is 52.26 (9)°. The ethyl ester group is approximately planar (r.m.s. deviation 0.0568 Å) and subtends an angle 67.73 (8)° to the pyrazole ring. In the crystal, molecules are linked by pairs of N—H...O hydrogen bonds, forming inversion dimers with anR22(10) ring motif. Weaker C—H...O contacts link these dimers into a three-dimensional network of molecules stacked along thea-axis direction. Offset π–π stacking interactions between the benzene rings [centroid-to-centroid distance = 3.8832 (12) Å] further stabilize the crystal packing.

scholarly journals Hirshfeld surface analysis and crystal structure of 7-methoxy-5-methyl-2-phenyl-11,12-dihydro-5,11-methano-1,2,4-triazolo[1,5-c][1,3,5]benzoxadiazocine

2018 ◽  
Vol 74 (9) ◽  
pp. 1211-1214 ◽  
Author(s):  
Mustafa Kemal Gumus ◽  
Sevgi Kansiz ◽  
Necmi Dege ◽  
Valentina A. Kalibabchuk
Keyword(s):  
Hydrogen Bonds ◽  
Surface Analysis ◽  
Crystal Packing ◽  
Three Dimensional ◽  
Triazole Ring ◽  
Hirshfeld Surface ◽  
Hirshfeld Surface Analysis ◽  
Supramolecular Network ◽  
Compound C ◽  
Benzene Rings

The title compound, C19H18N4O2, crystallizes with two independent molecules in the asymmetric unit. The triazole ring is inclined to the benzene rings by 9.63 (13) and 87.37 (12)° in one molecule, and by 4.46 (13) and 86.15 (11)° in the other. In the crystal, classical N—H...N hydrogen bonds, weak C—H...O hydrogen bonds and weak C—H...π interactions link the molecules into a three-dimensional supramolecular network. Hirshfeld surface analysis and two-dimensional fingerprint plots were used to investigate the intermolecular interactions present in the crystal, indicating that the most important contributions for the crystal packing are from H...H (51.4%), H...C/C...H (26.7%), H...O/O...H (8.9%) and H...N/N...H (8%) interactions.

scholarly journals Crystal structures of isomeric 4-bromo-N-[(2-nitrophenyl)sulfonyl]benzamide and 4-bromo-N-[(4-nitrophenyl)sulfonyl]benzamide

2017 ◽  
Vol 73 (3) ◽  
pp. 314-317
Author(s):  
S. Naveen ◽  
A. G. Sudha ◽  
E. Suresha ◽  
N. K. Lokanath ◽  
P. A. Suchetan ◽  
...  
Keyword(s):  
Benzoic Acid ◽  
Crystal Structures ◽  
Aromatic Ring ◽  
Dihedral Angle ◽  
Three Dimensional ◽  
Molecular Formula ◽  
Asymmetric Unit ◽  
Π Interactions ◽  
Benzene Rings ◽  
Independent Molecules

The syntheses and crystal structures of the isomeric 4-bromo-N-[(2-nitrophenyl)sulfonyl]benzamide, (I), and 4-bromo-N-[(4-nitrophenyl)sulfonyl]benzamide, (II), are described (molecular formula = C13H9BrN2O5S in each case). The asymmetric unit of (I) contains two independent molecules [(IA) and (IB)], while that of (II) contains one molecule. The benzoic acid aromatic ring of molecule (IA) is disordered due to rotation about the Car—C(=O) bond over two orientations in a 0.525 (9):0.475 (9) ratio. The dihedral angle between the benzene rings is 85.9 (3)° in (IA) and 65.22 (19)° in (IB), while in (II), the corresponding value is 56.7 (7)°. In the crystals of (I) and (II), N—H...O, C—H...O and C—H...π interactions generate three-dimensional networks.

scholarly journals Diaqua[5,10,15,20-tetrakis(4-chlorophenyl)porphyrinato-κ4N]iron(III) trifluoromethanesulfonate–4-hydroxy-3-methoxybenzaldehyde–water (1/1/2)

2014 ◽  
Vol 70 (8) ◽  
pp. m296-m297 ◽  
Author(s):  
Leila Ben Haj Hassen ◽  
Khaireddine Ezzayani ◽  
Yoann Rousselin ◽  
Habib Nasri
Keyword(s):  
Hydrogen Bonds ◽  
Crystal Packing ◽  
Three Dimensional ◽  
Octahedral Geometry ◽  
Distorted Octahedral Geometry ◽  
Water Molecules ◽  
Supramolecular Architecture ◽  
Centroid Distance ◽  
Distorted Octahedral ◽  
Benzene Rings

In the title compound, [Fe(C44H24Cl4N4)(H2O)2](SO3CF3)·C8H8O3·2H2O, the FeIIIcation is chelated by the four N atoms of the deprotonated tetrakis(4-chlorotetraphenyl)porphyrin (TClPP) and further coordinated by two water molecules in a distorted octahedral geometry. In the crystal, the cations, anions, 4-hydroxy-3-methoxybenzaldehyde and water molecules of crystallization are linked by classical O—H...O hydrogen bonds and weak C—H...O and C—H...Cl hydrogen bonds into a three-dimensional supramolecular architecture. The crystal packing is further stabilized by weak C—H...π interactions involving pyrrole and benzene rings. π–π stacking between parallel benzene rings of adjacent 4-hydroxy-3-methoxybenzaldehyde molecules is also observed, the centroid–centroid distance being 3.8003 (13) Å. The three F atoms of the anion are disordered over two sets of sites, with a refined occupancy ratio 0.527 (12):0.473 (12). The O atom of one water molecule of crystallization is also disordered over two positions in an occupancy ratio of 0.68 (5):0.32 (5).

scholarly journals (2-{[4-(Chloridomercuryl)phenyl]iminomethyl}pyridine-κ2N,N′)diiodidomercury(II) dimethyl sulfoxide monosolvate

2013 ◽  
Vol 69 (12) ◽  
pp. m633-m634
Author(s):  
Tushar S. Basu Baul ◽  
Imliwati Longkumer ◽  
Seik Weng Ng ◽  
Edward R. T. Tiekink
Keyword(s):  
Dimethyl Sulfoxide ◽  
Crystal Packing ◽  
Three Dimensional ◽  
Acute Angle ◽  
Tetrahedral Coordination ◽  
Secondary Interactions ◽  
Centroid Distance ◽  
Benzene Rings ◽  
Cl Atoms ◽  
Distorted Tetrahedral Coordination

The title dimethyl sulfoxide solvate, [Hg2(C12H9ClN2)I2]·C2H6OS, features tetrahedrally and linearly coordinated HgIIatoms. The distorted tetrahedral coordination sphere is defined by chelating N atoms that define an acute angle [69.6 (3)°] and two I atoms that form a wide angle [142.80 (4)°]. The linearly coordinated HgIIatom [177.0 (4)°] exists with a donor set defined by C and Cl atoms. Secondary interactions are apparent in the crystal packing with the tetrahedrally and linearly coordinated HgIIatoms expanding their coordination environments by forming weak Hg...I [3.772 (7) Å] and Hg...O [2.921 (12) Å] interactions, respectively. Mercury-containing molecules stack along theaaxis, are connected by π–π interactions [inter-centroid distance between pyridine and benzene rings = 3.772 (7) Å] and define channels in which the dimethyl sulfoxide molecules reside. The latter are connected by the aforementioned Hg...O interactions as well as C—H...I and C—H...O interactions, resulting in a three-dimensional architecture.

scholarly journals Synthesis, crystal structures and Hirshfeld surface analysis of 1,4-dibenzyl-6-methyl-1,4-dihydroquinoxaline-2,3-dione

2020 ◽  
Vol 76 (8) ◽  
pp. 1361-1364
Author(s):  
Emine Berrin Cinar ◽  
Ayman Zouitini ◽  
Youssef Kandri Rodi ◽  
Younes Ouzidan ◽  
Jérôme Marrot ◽  
...  
Keyword(s):  
Hydrogen Bonds ◽  
Surface Analysis ◽  
Network Structure ◽  
Crystal Packing ◽  
Three Dimensional ◽  
Hirshfeld Surface ◽  
Hirshfeld Surface Analysis ◽  
Dimensional Network ◽  
Benzene Rings ◽  
The Mean

The title quinoxaline molecule, C23H20N2O2, is not planar, the dihedral angle angle between the mean planes of the benzene rings being 72.54 (15)°. In the crystal, molecules are connected into chains extending parallel to (10\overline{1}) by weak C—H...O hydrogen bonds. Weak C—H...π interactions link the chains, forming a three-dimensional network structure. Hirshfeld surface analysis revealed that the most important contributions for the crystal packing are from H...H (48.7%), H...C/C...H (32.0%), H...O/O...H (15.4%), C...C (1.9%), H...N/N...H (1.1%) contacts.

scholarly journals Crystal structures of 4-methoxy-N-(4-methylphenyl)benzenesulfonamide andN-(4-fluorophenyl)-4-methoxybenzenesulfonamide

2015 ◽  
Vol 71 (11) ◽  
pp. 1388-1391
Author(s):  
Vinola Z. Rodrigues ◽  
C. P. Preema ◽  
S. Naveen ◽  
N. K. Lokanath ◽  
P. A. Suchetan
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Crystal Structures ◽  
Dihedral Angle ◽  
Crystal Packing ◽  
Three Dimensional ◽  
Supramolecular Architecture ◽  
One Dimensional ◽  
Ring Form ◽  
Benzene Rings

Crystal structures of twoN-(aryl)arylsulfonamides, namely, 4-methoxy-N-(4-methylphenyl)benzenesulfonamide, C14H15NO3S, (I), andN-(4-fluorophenyl)-4-methoxybenzenesulfonamide, C13H12FNO3S, (II), were determined and analyzed. In (I), the benzenesulfonamide ring is disordered over two orientations, in a 0.516 (7):0.484 (7) ratio, which are inclined to each other at 28.0 (1)°. In (I), the major component of the sulfonyl benzene ring and the aniline ring form a dihedral angle of 63.36 (19)°, while in (II), the planes of the two benzene rings form a dihedral angle of 44.26 (13)°. In the crystal structure of (I), N—H...O hydrogen bonds form infiniteC(4) chains extended in [010], and intermolecular C—H...πarylinteractions link these chains into layers parallel to theabplane. The crystal structure of (II) features N—H...O hydrogen bonds forming infinite one dimensionalC(4) chains along [001]. Further, a pair of C—H...O intermolecular interactions consolidate the crystal packing of (II) into a three-dimensional supramolecular architecture.

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