Interplay between packing, dimer interaction energy and morphology in a series of tricyclic imide crystals

Author(s):  
Maura Malinska ◽  
Aleksandra Kieliszek ◽  
Anna E. Kozioł ◽  
Barbara Mirosław ◽  
Krzysztof Woźniak

Crystal morphology is a very important feature in many industrial applications. Tricyclic imides, derivatives of 10-oxa-4-azatricyclo[5.2.1.02,6]dec-8-ene-3,5-dione with differing small hydrophobic groups (Me, Et), were studied and grouped based on Etter's rule. Using experimental X-ray studies, dimer energy calculations, framework analysis and periodic DFT-D calculations, it is shown that knowledge of the hydrogen-bond pattern can be used to determine the final crystal shape. Molecules forming a ring hydrogen-bond motif crystallize as plate crystals with the {100} facet as the slowest growing, whereas those molecules forming an infinite hydrogen-bond motif in the crystal structure crystallize as needles with the {101} facet having the largest surface area.

CrystEngComm ◽  
2015 ◽  
Vol 17 (4) ◽  
pp. 753-763 ◽  
Author(s):  
German L. Perlovich ◽  
Alex M. Ryzhakov ◽  
Valery V. Tkachev ◽  
Alexey N. Proshin

The crystal structures of six adamantane derivatives of sulfonamides have been determined by X-ray diffraction and their sublimation and fusion processes have been studied.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Hui-Jing Li ◽  
Jun-Li Wang ◽  
Rui Wang ◽  
Dong-Hui Luo ◽  
Yan-Chao Wu

4H-Chromene-2-carboxylic acid ester derivatives of renieramycin M might be of use for the structural-activity relationship studies of antitumor antibiotic tetrahydroisoquinoline natural products. Accordingly, 6-tert-butyl-4-phenyl-4H-chromene-2-carboxylic acid, one key intermediate, was synthesized via the condensation of (3E)-2-oxo-4-phenylbut-3-enoate methyl ester with 4-tert-butylphenol in the presence of AuCl3/3AgOTf (5 mol%), followed by cyclodehydration and aqueous hydrolysis. The product was unambiguously shown to the 4H-chromene-2-carboxylic acid by spectroscopy and X-ray crystallographic analysis. A packing diagram of the crystal structure shows that aromaticπ-stacking interactions and O–H⋯O hydrogen bond stabilize the structure in the solid.


2004 ◽  
Vol 60 (2) ◽  
pp. 191-196 ◽  
Author(s):  
Maciej Kubicki

The case of prototropic annular tautomerism in an imidazole derivative has been found. The crystal structure contains a 50:50 mixture of two tautomers: 4-nitro-5-methoxyimidazole and 5-nitro-4-methoxyimidazole. The X-ray experiment actually shows the superposition of these compounds; it appears as if the structure is centrosymmetric and the N—H hydrogen atoms are disordered over two ring N atoms. Owing to the hydrogen-bond pattern, the values of their site occupation factors have to be exactly equal to 1/2. The molecules are connected into a three-dimensional network by means of N—H...N and C—H...O hydrogen bonds.


2017 ◽  
Vol 73 (7) ◽  
pp. 508-516 ◽  
Author(s):  
Fahimeh Sabbaghi ◽  
Mehrdad Pourayoubi ◽  
Abolghasem Farhadipour ◽  
Nazila Ghorbanian ◽  
Pavel V. Andreev

In the structure of 2-(4-chloroanilino)-1,3,2λ4-diazaphosphol-2-one, C12H11ClN3OP, each molecule is connected with four neighbouring molecules through (N—H)2...O hydrogen bonds. These hydrogen bonds form a tubular arrangement along the [001] direction built from R 3 3(12) and R 4 3(14) hydrogen-bond ring motifs, combined with a C(4) chain motif. The hole constructed in the tubular architecture includes a 12-atom arrangement (three P, three N, three O and three H atoms) belonging to three adjacent molecules hydrogen bonded to each other. One of the N—H groups of the diazaphosphole ring, not co-operating in classical hydrogen bonding, takes part in an N—H...π interaction. This interaction occurs within the tubular array and does not change the dimension of the hydrogen-bond pattern. The energies of the N—H...O and N—H...π hydrogen bonds were studied by NBO (natural bond orbital) analysis, using the experimental hydrogen-bonded cluster of molecules as the input file for the chemical calculations. In the 1H NMR experiment, the nitrogen-bound proton of the diazaphosphole ring has a high value of 17.2 Hz for the 2 J H–P coupling constant.


1995 ◽  
Vol 50 (4) ◽  
pp. 488-502 ◽  
Author(s):  
Klaus Angermund ◽  
Anette Eckerle ◽  
Frank Lutz

The hydrovinylation of styrene can be catalyzed by the addition of phosphane-modified Ni(II) compounds with high reactivity and enantioselectivity if the azaphospholene 1 is used as P-component of the catalysts. Until recently the industrial applications of 1 have been hampered by its difficult synthesis. To search for easier to synthesize, but equally well catalyzing derivatives of 1 a molecular modelling study was carried out. Based on already experimentally tested and structurally characterized azaphospholenes a model is developed, which not only leads to a better understanding of the catalytic process and but also to a relatively easy way to predict catalytic properties in these systems. Using an extended, customized valence force field several new derivatives of 1 have been tested. Their predicted and experimentally determined catalytic properties are in good agreement. The X-ray structures of the phenyl-substituted, monomeric azaphospholene 13, which hitherto results in the second best catalyst, and of its precursor 19 are presented.


Author(s):  
Yusuke Nakatake ◽  
Makoto Okabe ◽  
Shota Sato

Abstract In this paper, we carried out PIND (Particle Impact Noise Detection) test and X-ray inspection of a transistor in a TO-18 package for commercial and industrial applications. From our evaluation results, we explain the validity of the PIND test by comparing PIND test and X-ray inspection results. We make clear that PIND test is able to detect internal foreign material that may be transparent to X-ray inspection. In addition, we report analysis results of internal foreign materials from defective devices. This matter suggests that a problem is contamination control in the manufacturing process, most likely the sealing process.


2021 ◽  
Vol 7 (8) ◽  
pp. 110
Author(s):  
Songjie Yang ◽  
Matteo Zecchini ◽  
Andrew Brooks ◽  
Sara Krivickas ◽  
Desiree Dalligos ◽  
...  

The syntheses of new BEDT-TTF derivatives are described. These comprise BEDT-TTF with one ethynyl group (HC≡C-), with two (n-heptyl) or four (n-butyl) alkyl side chains, with two trans acetal (-CH(OMe)2) groups, with two trans aminomethyl (-CH2NH2) groups, and with an iminodiacetate (-CH2N(CH2CO2−)2 side chain. Three transition metal salts have been prepared from the latter donor, and their magnetic properties are reported. Three tris-donor systems are reported bearing three BEDT-TTF derivatives with ester links to a core derived from benzene-1,3,5-tricarboxylic acid. The stereochemistry and molecular structure of the donors are discussed. X-ray crystal structures of two BEDT-TTF donors are reported: one with two CH(OMe)2 groups and with one a -CH2N(CH2CO2Me)2 side chain.


Author(s):  
Fabian Jaeger ◽  
Alessandro Franceschi ◽  
Holger Hoche ◽  
Peter Groche ◽  
Matthias Oechsner

AbstractCold extruded components are characterized by residual stresses, which originate from the experienced manufacturing process. For industrial applications, reproducibility and homogeneity of the final components are key aspects for an optimized quality control. Although striving to obtain identical deformation and surface conditions, fluctuation in the manufacturing parameters and contact shear conditions during the forming process may lead to variations of the spatial residual stress distribution in the final product. This could lead to a dependency of the residual stress measurement results on the relative axial and circumferential position on the sample. An attempt to examine this problem is made by the employment of design of experiments (DoE) methods. A statistical analysis of the residual stress results generated through X-Ray diffraction is performed. Additionally, the ability of cold extrusion processes to generate uniform stress states is analyzed on specimens of austenitic stainless steel 1.4404 and possible correlations with the pre-deformed condition are statistically examined. Moreover, the influence of the coating, consisting of oxalate and a MoS2 based lubricant, on the X-Ray diffraction measurements of the surface is investigated.


2020 ◽  
Vol 18 (1) ◽  
pp. 951-961
Author(s):  
Qiuju Chen ◽  
Tao Hui ◽  
Hongjuan Sun ◽  
Tongjiang Peng ◽  
Wenjin Ding

AbstractVarious morphologies of magnesium carbonate hydrate had been synthesized without using any organic additives by carefully adjusting the reaction temperature and time during the talc carbonation process. At lower temperatures, magnesium carbonate hydrate was prone to display needle-like morphology. With the further increase of the carbonation temperature, the sheet-like crystallites became the preferred morphology, and at higher aging temperatures, these crystallites tended to assemble into layer-like structures with diverse morphologies, such as rose-like particles and nest-like structure. The reaction time had no effect on the crystal morphology, but it affected the particle size and situation of the crystal growth. X-Ray diffraction results showed that these various morphologies were closely related to their crystal structure and compositions. The needle-like magnesium carbonate hydrate had a formula of MgCO3·3H2O, whereas with the morphological transformation from needle-like to sheet-like, rose-like, and nest-like structure, their corresponding compositions also changed from MgCO3·3H2O to 4MgCO3·Mg(OH)2·8H2O, 4MgCO3·Mg(OH)2·5H2O, and 4MgCO3·Mg(OH)2·4H2O.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Robert Christie ◽  
Adrian Abel

Abstract This chapter provides an overview of the structural and synthetic chemistry, and the industrial applications, of dioxazine pigments, a small group of high performance organic pigments. The color violet (or purple) has frequently assumed a prominent position in history, on account of its rarity and cost. The natural colorant Tyrian purple and the first synthetic textile dye, Mauveine, are prime examples of this unique historical feature. CI Pigment Violet 23, also referred to as Dioxazine Violet or Carbazole Violet, is one of the most universally used organic pigments, by far the most important industrial pigment in the violet shade area. Dioxazine Violet is also unique as the dominant industrial violet pigment providing a brilliant, intense violet color and an excellent all-round set of fastness properties. The pigment has a polycyclic molecular structure, originally described wrongly as a linear arrangement, and later shown to adopt an S-shaped arrangement on the basis of X-ray structural analysis. Two other dioxazine pigments are of rather lesser importance. The synthesis and manufacturing route to CI Pigment Violet 23 is described in the review. Finally, a survey of the principal current applications of the individual dioxazine pigments is presented.


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