scholarly journals The reaction of anthracyl-α-hydroxyphosphonate with anthracene: Facile Access to diverse (bis)-anthracylphosphonates as a suitable source for useful extensive π-conjugates

2019 ◽  
Author(s):  
Moghal Zubair Khalid Baig ◽  
Banchanidhi Prusti ◽  
Shouvik Bhuin ◽  
Manab Chakravarty
Keyword(s):  
Molecular Conformation ◽  
Product Formation ◽  
Molecular Structures ◽  
Aggregation Induced Emission ◽  
X Ray ◽  
Bond Angles ◽  
Nucleophilic Center

Molecular anthracene has been used as arene in the Friedel-Crafts (FC) type arylation reaction of anthracyl-α-hydroxyphosphonate in the presence of acid. A diverse product formation is observed, in which anthracene unit is found to be linked through its C1 position with α-C of phosphonate. Interestingly, the molecular conformation (X-ray structure) of this phosphonate reveals one of the bond angles of a tetrahedral carbon as 118o which is close to the C of sp 2 character. The attacks from C1, C2 or C9 nucleophilic center of molecular anthracene to C10 atom of 9-anthrylphosphonate are also recognized. The diverse molecular structures are established spectroscopically. The bis-anthracyl compounds with a P-CH2 unit have been successfully utilized in Horner-Wadsworth-Emmons (HWE) reactions to afford extensive bis-anthracyl-linked π-conjugates. Thus, the electronically different substituent is attached to the system by varying the aldehydes. Among all these π-conjugates, the compound with three anthracyl core is noticed as a weak AIEgen (Aggregation-Induced emission active fluorogen).

scholarly journals X-ray Structural Analyses of Two Allotropes of Cycloheptasulfur ( γ and δ-S7 ) [1]

1980 ◽  
Vol 35 (11) ◽  
pp. 1378-1383 ◽  
Author(s):  
Ralf Steudel ◽  
Jürgen Steidel ◽  
Joachim Pickardt ◽  
Fritz Schuster ◽  
Richard Reinhardt
Keyword(s):  
Molecular Structures ◽  
X Ray ◽  
Bond Angles ◽  
Torsional Angles

Abstract X-ray structural analyses of two monoclinic allotropes of cycloheptasulfur carried out at -110 °C revealed almost identical chair-like molecular structures of approximate Cs symmetry with bond distances between 199.5 and 218.2 pm, bond angles between 101.5 and 107.5°, and torsional angles between 0 and 109°.

Molecular Structures of p-Methylsulphonylbenzoic Acid and Methylphenylsulphone: Comparison of X-Ray and Electron Diffraction Results

1984 ◽  
Vol 39 (5) ◽  
pp. 607-609 ◽  
Author(s):  
Jon Brunvoll ◽  
Marcello Colapietro ◽  
Aldo Domenicano ◽  
Clara Marciante ◽  
Gustavo Portalone ◽  
...  
Keyword(s):  
Electron Diffraction ◽  
Benzene Ring ◽  
Bond Distance ◽  
Molecular Structures ◽  
Gas Electron Diffraction ◽  
Free Molecule ◽  
X Ray ◽  
Bond Angles ◽  
X Ray Crystallography ◽  
Systematic Effects

The molecular structures of p-methylsulphonylbenzoic acid and methylphenylsulphone have been accurately determined by X-ray crystallography and gas electron diffraction, respectively. After correction for systematic effects, the geometry of the crystal molecule is seen to agree with that of the free molecule within a few thousandths of an Å unit for bond distances and a few tenths of a degree for bond angles. An exception is the S-Me bond distance, which is ca. 0.02 Å shorter in the crystal. The distortion of the benzene ring angles from 120°, an effect of the - SO2Me substituent, is virtually the same from both experiments

Crystal structure determination of the conformation of two bicyclo[3.3.1]nonan-ones

1985 ◽  
Vol 63 (6) ◽  
pp. 1166-1169 ◽  
Author(s):  
John F. Richardson ◽  
Ted S. Sorensen
Keyword(s):  
Crystal Structure ◽  
Direct Methods ◽  
Chair Conformation ◽  
Molecular Structures ◽  
Boat Conformation ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Final Agreement

The molecular structures of exo-7-methylbicyclo[3.3.1]nonan-3-one, 3, and the endo-7-methyl isomer, 4, have been determined using X-ray-diffraction techniques. Compound 3 crystallizes in the space group [Formula: see text] with a = 15.115(1), c = 7.677(2) Å, and Z = 8 while 4 crystallizes in the space group P21 with a = 6.446(1), b = 7.831(1), c = 8.414(2) Å, β = 94.42(2)°, and Z = 2. The structures were solved by direct methods and refined to final agreement factors of R = 0.041 and R = 0.034 for 3 and 4 respectively. Compound 3 exists in a chair–chair conformation and there is no significant flattening of the chair rings. However, in 4, the non-ketone ring is forced into a boat conformation. These results are significant in interpreting what conformations may be present in the related sp2-hybridized carbocations.

scholarly journals β-Ketophosphonates with Pentalenofuran Scaffolds Linked to the Ketone Group for the Synthesis of Prostaglandin Analogs

2021 ◽  
Vol 22 (13) ◽  
pp. 6787
Author(s):  
Constantin I. Tănase ◽  
Constantin Drăghici ◽  
Miron Teodor Căproiu ◽  
Anamaria Hanganu ◽  
Gheorghe Borodi ◽  
...  
Keyword(s):  
Lithium Salt ◽  
Methyl Esters ◽  
Secondary Compounds ◽  
Molecular Structures ◽  
Keto Group ◽  
High Yield ◽  
Oxidation Reactions ◽  
Prostaglandin Analogues ◽  
X Ray ◽  
Oxidation Of Alcohols

β-Ketophosphonates with pentalenofurane fragments linked to the keto group were synthesized. The bulky pentalenofurane skeleton is expected to introduce more hindrance in the prostaglandin analogues of type III, greater than that obtained with the bicyclo[3.3.0]oct(a)ene fragments of prostaglandin analogues I and II, to slow down (retard) the inactivation of the prostaglandin analogues by oxidation of 15α-OH to the 15-keto group via the 15-PGDH pathway. Their synthesis was performed by a sequence of three high yield reactions, starting from the pentalenofurane alcohols 2, oxidation of alcohols to acids 3, esterification of acids 3 to methyl esters 4 and reaction of the esters 4 with lithium salt of dimethyl methanephosphonate at low temperature. The secondary compounds 6b and 6c were formed in small amounts in the oxidation reactions of 2b and 2c, and the NMR spectroscopy showed that their structure is that of an ester of the acid with the starting alcohol. Their molecular structures were confirmed by single crystal X-ray determination method for 6c and XRPD powder method for 6b.

Synthesis, structural characterization and catalytic activity of chlororuthenium(II) complexes with substituted Schiff base/phosphine ancillary ligands

2020 ◽  
Vol 75 (9-10) ◽  
pp. 851-857
Author(s):  
Chong Chen ◽  
Fule Wu ◽  
Jiao Ji ◽  
Ai-Quan Jia ◽  
Qian-Feng Zhang
Keyword(s):  
Schiff Base ◽  
Catalytic Activity ◽  
Structural Characterization ◽  
Room Temperature ◽  
Molecular Structures ◽  
Cationic Complex ◽  
Neutral Complex ◽  
Ancillary Ligands ◽  
X Ray ◽  
X Ray Crystallography

AbstractTreatment of [(η6-p-cymene)RuCl2]2 with one equivalent of chlorodiphenylphosphine in tetrahydrofuran at reflux afforded a neutral complex [(η6-p-cymene)RuCl2(κ1-P-PPh2OH)] (1). Similarly, the reaction of [Ru(bpy)2Cl2·2H2O] (bpy = 2,2′-bipyridine) and chlorodiphenylphosphine in methanol gave a cationic complex [Ru(bpy)2Cl(κ1-P-PPh2OCH3)](PF6) (2), while treatment of [RuCl2(PPh3)3] with [2-(C5H4N)CH=N(CH2)2N(CH3)2] (L1) in tetrahydrofuran at room temperature afforded a ruthenium(II) complex [Ru(PPh3)Cl2(κ3-N,N,N-L1)] (3). Interaction of the chloro-bridged complex [Ru(CO)2Cl2]n with one equivalent of [Ph2P(o-C6H4)CH=N(CH2)2N(CH3)2] (L2) led to the isolation of [Ru(CO)Cl2(κ3-P,N,N-L2)] (4). The molecular structures of the ruthenium(II) complexes 1–4 have been determined by single-crystal X-ray crystallography. The properties of the ruthenium(II) complex 4 as a hydrogenation catalyst for acetophenone were also tested.

Organic chemistry lecture course and exercises based on true scale models

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Felix Lederle ◽  
Eike G. Hübner
Keyword(s):  
Organic Chemistry ◽  
Bond Length ◽  
3D Models ◽  
Poly Lactic Acid ◽  
X Ray ◽  
Bond Angles ◽  
Chemical Structures ◽  
Scale Models ◽  
Hands On ◽  
Scaled Models

Abstract3D models of chemical structures are an important tool for chemistry lectures and exercises. Usually, simplified models based on standard bond length and angles are used. These models allow for a visualized discussion of (stereo)chemical aspects, but they do not represent the true spatial conditions. 3D-printing technologies facilitate the production of scale models. Several protocols describe the process from X-ray structures, calculated geometries or virtual molecules to printable files. In contrast, only a few examples describe the integration of scaled models in lecture courses. True bond angles and scaled bond lengths allow for a detailed discussion of the geometry and parameters derived therefrom, for example double bond character, aromaticity and many more. Here, we report a complete organic chemistry/stereochemistry lecture course and exercise based on a set of 37 scale models made from poly(lactic acid) as sustainable material. All models have been derived from X-ray structures and quantum chemical calculations. Consequently, the models reflect the true structure as close as possible. A fixed scaling factor of 1 : 1.8·108 has been applied to all models. Hands-on measuring of bond angles and bond length leads to an interactive course. The course has been evaluated with a very positive feedback.

scholarly journals Synthesis, Cytotoxic Activity, Crystal Structure, DFT Studies and Molecular Docking of 3-Amino-1-(2,5-dichlorophenyl)-8-methoxy-1H-benzo[f]chromene-2-carbonitrile

Crystals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 184
Author(s):  
Menna El Gaafary ◽  
Tatiana Syrovets ◽  
Hany M. Mohamed ◽  
Ahmed A. Elhenawy ◽  
Ahmed M. El-Agrody ◽  
...  
Keyword(s):  
Cytotoxic Activity ◽  
Cell Lines ◽  
Cancer Cell ◽  
Dna Methyltransferase ◽  
Human Cancer ◽  
Theoretical Calculations ◽  
Cancer Cell Lines ◽  
Molecular Structures ◽  
Cytotoxic Activities ◽  
X Ray

The target compound 3-amino-1-(2,5-d ichlorophenyl)-8-methoxy-1H-benzo[f]-chromene-2-carbonitrile (4) was synthesized via a reaction of 6-methoxynaphthalen-2-ol (1), 2,5-dichlorobenzaldehyde (2), and malononitrile (3) in ethanolic piperidine solution under microwave irradiation. The newly synthesized β-enaminonitrile was characterized by FT-IR, 1H NMR, 13C NMR, mass spectroscopy, elemental analysis and X-ray diffraction data. Its cytotoxic activity was evaluated against three different human cancer cell lines MDA-MB-231, A549, and MIA PaCa-2 in comparison to the positive controls etoposide and camptothecin employing the XTT cell viability assay. The analysis of the Hirshfeld surface was utilized to visualize the reliability of the crystal package. The obtained results confirmed that the tested molecule revealed promising cytotoxic activities against the three cancer cell lines. Furthermore, theoretical calculations (DFT) were carried out with the Becke3-Lee-Yang-parr (B3LYP) level using 6-311++G(d,p) basis. The optimization geometry for molecular structures was in agreement with the X-ray structure data. The HOMO-LUMO energy gap of the studied system was discussed. The intermolecular-interactions were studied through analysis of the topological-electron-density(r) using the QTAIM and NCI methods. The novel compound exhibited favorable ADMET properties and its molecular modeling analysis showed strong interaction with DNA methyltransferase 1.

scholarly journals Structure of Plasma (re)Polymerized Polylactic Acid Films Fabricated by Plasma-Assisted Vapour Thermal Deposition

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 459
Author(s):  
Zdeněk Krtouš ◽  
Lenka Hanyková ◽  
Ivan Krakovský ◽  
Daniil Nikitin ◽  
Pavel Pleskunov ◽  
...  
Keyword(s):  
Polylactic Acid ◽  
Photoelectron Spectroscopy ◽  
Vapour Deposition ◽  
Chemical Vapour ◽  
Molecular Structures ◽  
Plasma Polymers ◽  
Thermal Deposition ◽  
X Ray ◽  
Process Chemistry ◽  
Precursor Molecules

Plasma polymer films typically consist of very short fragments of the precursor molecules. That rather limits the applicability of most plasma polymerisation/plasma-enhanced chemical vapour deposition (PECVD) processes in cases where retention of longer molecular structures is desirable. Plasma-assisted vapour thermal deposition (PAVTD) circumvents this limitation by using a classical bulk polymer as a high molecular weight “precursor”. As a model polymer in this study, polylactic acid (PLA) has been used. The resulting PLA-like films were characterised mostly by X-ray photoelectron spectroscopy (XPS) and nuclear magnetic resonance (NMR) spectroscopy. The molecular structure of the films was found to be tunable in a broad range: from the structures very similar to bulk PLA polymer to structures that are more typical for films prepared using PECVD. In all cases, PLA-like groups are at least partially preserved. A simplified model of the PAVTD process chemistry was proposed and found to describe well the observed composition of the films. The structure of the PLA-like films demonstrates the ability of plasma-assisted vapour thermal deposition to bridge the typical gap between the classical and plasma polymers.

Strukturuntersuchungen an Diaryldichalkogeniden: Die Molekülstrukturen von [2,4,6-(CF3)3C6H2S]2,[2,4,6-Me3C6H2Te]2 und [2-Me2N-4,6-(CF3)2C6H2Te]2 / Structural Investigations of Diaryl Dichalcogenides: The Molecular Structures of [2,4,6-(CF3)3C6H2S]2, [2,4,6-Me3C6H2Te]2 and [2-Me2N-4,6-(CF3)2C6H2Te]2

1992 ◽  
Vol 47 (3) ◽  
pp. 305-309 ◽  
Author(s):  
Anja Edelmann ◽  
Sally Brooker ◽  
Norbert Bertel ◽  
Mathias Noltemeyer ◽  
Herbert W. Roesky ◽  
...  
Keyword(s):  
Molecular Structures ◽  
Monoclinic Space Group ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
Orthorhombic Space Group ◽  
Structural Investigations ◽  
Space Group ◽  
X Ray

Abstract The Molecular Structures of [2,4,6-(CF3)3C6H2S]2 (1) [2,4,6-Me3C6H2Te]2 and [2-Me2N-4,6-(CF3)2C6H2Te]2 (3) have been determined by X-ray diffraction. Crystal data: 1: orthorhombic, space group P212121, Z = 4, a = 822.3(2), b = 1029.2(2), c = 2526.6(5) pm (2343 observed independent reflexions, R = 0.042); 2: orthorhombic, space group Iba 2, Z = 8, a = 1546.5(2), b = 1578.4(2), c = 1483.9(1) pm (2051 observed independent reflexions, R = 0.030); 3: monoclinic, space group P 21/c, Z = 4, a = 1118.7(1), b = 1536.5(2), c = 1492.6(2) pm, β = 98.97(1)° (3033 observed independent reflexions, R = 0.025).

Sign in / Sign up

Export Citation Format

Share Document