Oxazoles XXII. The Cobalt(II) Coordination Chemistry of 2-(ortho-Anilinyl)-4,4-dimethyl-2-oxazoline: Syntheses, Properties, and Solid-State Structural Characterization

2010 ◽  
Vol 63 (1) ◽  
pp. 47 ◽  
Author(s):  
Felix J. Baerlocher ◽  
Robert Bucur ◽  
Andreas Decken ◽  
Charles R. Eisnor ◽  
Robert A. Gossage ◽  
...  
Keyword(s):  
Solid State ◽  
Gas Phase ◽  
Octahedral Complex ◽  
Conductivity Measurements ◽  
Visible Spectroscopy ◽  
X Ray ◽  
Cobalt Compounds ◽  
Uv Visible ◽  
Solid State Structures ◽  
Cobaltous Nitrate

Ethanol solutions of the cobalt(ii) halides react with an excess of 2-(ortho-anilinyl)-4,4-dimethyl-2-oxazoline (1: i.e. 2-(2′-anilinyl)-4,4-dimethyl-4,5-dihydro-1,3-oxazole) to give isolable κ2-N,N′-bonded species of 1 in good to excellent yields. The complexes CoX2(1-κ2-N,N′)·(H2O) n have been isolated for X = Cl (2: n = 1/2), X = Br and I (3 and 4, respectively; n = 0); the solid-state structures (X-ray) are in accordance with those suggested by UV-visible spectroscopy and conductivity measurements (i.e. non-ionic complexes with a pseudo-tetrahedral coordination motif around Co). In contrast, reaction of excess 1 with Co(NCS)2 forms the octahedral (UV-visible, X-ray) bis-isothiocyanato complex Co(NCS-κ1-N′)2(1-κ2-N,N′)2 (5) with cis-oriented NCS groups and trans-disposed oxazolines. Calculations at the PM3(tm) level of theory suggest that this isomer is close in energy to the four other possible (gas-phase) isomers. Treatment of ethanol solutions of hydrated cobaltous nitrate with excess 1 yields a material analyzed as [Co(NO3)(1)(H2O)2](NO3) (6a) and a small amount (less than 1%) of a second complex (6b); the latter has been characterized (X-ray) as the hydrated octahedral complex [Co(NO3-κ1-O)(1-κ2-N,N′)2(OH2)](NO3). In this case, the nitrato and aqua groupings are located cis to one another and trans to the coordinated –NH2 groups. Complex 6a is surmised to have a [Co(NO3-κ2-O,O′)2(1-κ2-N,N′)(OH2)2]NO3 structure. Cobalt compounds 2–5 and 1 have also been screened for their antifungal properties against Aspergillus niger, Aspergillus flavus, Candida albicans, and Saccharomyces cerevisiae but were found to be inactive in this regard.

scholarly journals Preparation and Properties of Rhodium(III) Complexes with the Tetradentate Ligand N,N'-Bis(2'-pyridinecarboxamide)-1,8-naphthalene

1994 ◽  
Vol 49 (1) ◽  
pp. 111-118 ◽  
Author(s):  
Evy Manessi-Zoupa ◽  
Theodoros F. Zafiropoulos ◽  
Spyros P. Perlepes
Keyword(s):  
Solid State ◽  
Chelating Agent ◽  
Bidentate Ligand ◽  
Octahedral Complex ◽  
Tetradentate Ligand ◽  
Conductivity Measurements ◽  
Nmr Studies ◽  
X Ray ◽  
H Nmr ◽  
Elemental Analyses

AbstractSynthetic procedures are described that allow access to a number of new Rh(III) complexes with the tetradentate bis-amide ligand N,N'-bis(2'-pyridinecarboxamide)-1,8-naphthalene (LH2). These complexes have the formulae Rh(LH2)Cl3, Na[RhLX2] • H2O (X = Cl, CN) and [RhLA2]ClO4 (A = pyridine, 1-methylbenzotriazole). The compounds have been characterized by elemental analyses, conductivity measurements, X-ray powder patterns, spectroscopic (IR, UV/VIS, 1H NMR) studies and electrochemical methods. The neutral amide behaves as a bis-bidentate ligand in the oligomeric or polymeric, octahedral complex Rh(LH2,)Cl3. Monomeric, trans octahedral structures are assigned for the complexes of L2− in the solid state; the doubly deprotonated ligand acts as a tetradentate chelating agent with the four nitrogens as ligating atoms.

Biocompatibility of Silver Nano Bio-conjugates from Vitis vinifera Seeds and its Major Component Resveratrol

2016 ◽  
Vol 6 (3) ◽  
Author(s):  
R. Preethi ◽  
P. Padma
Keyword(s):  
Zeta Potential ◽  
Vitis Vinifera ◽  
Silver Ions ◽  
Seed Extract ◽  
Polydispersity Index ◽  
Potential Range ◽  
Visible Spectroscopy ◽  
Grape Seeds ◽  
X Ray ◽  
Uv Visible

The study focused on the green synthesis of silver nanobioconjugates (AgNPs) from phenolic-rich fruit source, Vitis vinifera seed extract and its major component phenolic, resveratrol respectively. Sunlight exposure for 20 minutes was the method of choice for the synthesis of AgNPs of the extract as well as the phenolic, resveratrol. The synthesized nanobioconjugates were characterized using UV-Visible spectroscopy, Transmission electron microscopy (TEM), Energy dispersive X-ray analysis (EDAX), X-ray diffraction (XRD), Polydispersity index, Zeta potential and Fourier transform infrared spectroscopy (FTIR). The reduction of silver ions was confirmed by UV-visible spectroscopy with peaks at 440nm for both nanobioconjugates synthesized from seed extract and compound. The nanobioconjugates showed the spherical in shape with 14-35nm in size and crystalline in nature. The conjugates are well dispersed with 0.301 and 0.287 polydispersity index and the zeta potential range at -13.6 and -14.3mV for stability. The FTRI data proved that the components in grape seeds act as good reductants and stabilizers for the silver nanobioconjugate synthesis. All the synthesized nanobioconjugates exhibited steady and sustained release of the medicinal components conjugated, proving their druggability, and were biocompatible with human cells, demonstrating their safety. The findings of the study validate the anticancer properties of silver nanobioconjugates of Vitis vinifera and its active component resveratrol.

Evaluation of Antibacterial and Antidiabetic Potential of Silver Nanoparticles using Eugenia Uniflora L. Seed Extract

2020 ◽  
Vol 13 (6) ◽  
pp. 5217-5225
Author(s):  
Guru Kumar Dugganaboyana ◽  
Chethankumar Mukunda ◽  
Suresh Darshini Inakanally
Keyword(s):  
Biomedical Applications ◽  
Pathogenic Bacteria ◽  
Seed Extract ◽  
Drug Formulation ◽  
Visible Spectroscopy ◽  
Plant Materials ◽  
X Ray ◽  
Eugenia Uniflora ◽  
Uv Visible

In recent years, green nanotechnology-based approaches using plant materials have been accepted as an environmentally friendly and cost-effective approach with various biomedical applications. In the current study, AgNPs were synthesized using the seed extract of the Eugenia uniflora L. (E.uniflora). Characterization was done using UV-Visible spectroscopy, X-ray diffraction (XRD), scanning electronic microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) analyses. The formation of AgNPs has confirmed through UV-Visible spectroscopy (at 466 nm) by the change of color owing to surface Plasmon resonance. Based on the XRD pattern, the crystalline property of AgNPs was established. The functional group existing in seed of E.uniflora extract accountable for the reduction of Ag+ ion and the stabilization of AgNPs was investigated. The morphological structures and elemental composition was determined by SEM and EDX analysis. With the growing application of AgNPs in biomedical perspectives, the biosynthesized AgNPs were evaluated for their antibacterial and along with their antidiabetic potential. The results showed that AgNPs are extremely effective with potent antidiabetic potential at a very low concentration. It also exhibited potential antibacterial activity against the three tested human pathogenic bacteria. Overall, the results highlight the effectiveness and potential applications of AgNPs in biomedical fields such as in the treatment of acute illnesses as well as in drug formulation for treating various diseases such as cancer and diabetes. It could be concluded that E. uniflora seed extract AgNPs can be used efficiently for in vitro evaluation of their antibacterial and antidiabetic effects with potent biomedical applications.

scholarly journals Green synthesis of silk sericin-embedded silver nanoparticles and their antibacterial application against multidrug-resistant pathogens

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Md. Abdullah Al Masud ◽  
Hamid Shaikh ◽  
Md. Shamsul Alam ◽  
M. Minnatul Karim ◽  
M. Abdul Momin ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Green Synthesis ◽  
Bombyx Mori ◽  
Multidrug Resistant ◽  
Visible Spectroscopy ◽  
Silk Sericin ◽  
X Ray ◽  
Synthesis Strategy ◽  
Uv Visible ◽  
Multidrug Resistant Pathogens

Abstract Background The green synthesis strategy of metallic nanoparticles (NPs) has become popular due to being environmentally friendly. Stable silver nanoparticles (AgNPs) have been synthesized by natural products such as starch, soy protein, various extract of leaves, barks, and roots functioning both as reducing and stabilizing agents. Likewise, silk sericin (SS) is a globular protein discarded in the silk factory might be used for NP synthesis. In this research, we focus on the green synthesis and stabilization of AgNPs by SS as well as assessment of their antibacterial activities against some drug-resistant pathogen. Results SS was extracted from Bombyx mori silkworm cocoons in an aqueous medium. 17 w/w% of dry sericin powder with respect to the cocoon’s weight was obtained by freeze-drying. Furthermore, AgNPs conjugated to sericin, i.e., SS-capped silver nanoparticles (SS-AgNPs) were synthesized by easy, cost-effective, and environment-friendly methods. The synthesized SS-AgNPs were characterized by UV-visible spectroscopy, Fourier-transform infrared-attenuated total reflection (FTIR-ATR) spectroscopy, transmission electron microscopy (TEM), and X-ray diffraction measurement. It has been found from the absorbance of UV-visible spectroscopy that a higher percent of SS-AgNPs was obtained at a higher concentration of silver nitrate solution. FTIR-ATR spectra showed that the carboxylate groups obtained from silk sericin act as a reducing agent for the synthesis of silver nanoparticles, while NH2+ and COO− act as a stabilizer of AgNPs. The X-ray diffractogram of SS-AgNPs was quite different from AgNO3 and sericin due to a change in the crystal structure. The diameter of AgNPs was around 20–70 nm observed using TEM. The synthesized SS-AgNPs exhibited strong antibacterial activity against multidrug-resistant pathogens, Escherichia coli and Pseudomonas aeruginosa. Minimal inhibitory/bactericidal concentrations against E. coli and P. aeruginosa were 20μg/mL. Conclusions This study encourages the use of Bombyx mori for the ecofriendly synthesis of SS-AgNPs to control multidrug-resistant microorganisms.

Intramolecular London Dispersion Interaction Effects on Gas-Phase and Solid-State Structures of Diamondoid Dimers

2017 ◽  
Vol 139 (46) ◽  
pp. 16696-16707 ◽  
Author(s):  
Andrey A. Fokin ◽  
Tatyana S. Zhuk ◽  
Sebastian Blomeyer ◽  
Cristóbal Pérez ◽  
Lesya V. Chernish ◽  
...  
Keyword(s):  
Solid State ◽  
Gas Phase ◽  
Interaction Effects ◽  
Dispersion Interaction ◽  
London Dispersion ◽  
Solid State Structures

Synthesis and Characterization of Poly(azomethine)/ZnO Nanocomposite Toward Photocatalytic Degradation of Methylene Blue, Malachite Green, and Bismarck Brown

2019 ◽  
Vol 141 (5) ◽  
Author(s):  
S. J. Pradeeba ◽  
K. Sampath
Keyword(s):  
Methylene Blue ◽  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Fourier Transform Infrared Spectroscopy ◽  
Malachite Green ◽  
Fourier Transform Infrared ◽  
Visible Spectroscopy ◽  
X Ray ◽  
Natural Sunlight ◽  
Uv Visible

This research was carried out based on the significance of protecting the environment by preventing the contamination of water caused from effluents discharge from dyeing industries, effective nanocomposite were prepared to solve this problem. The poly(azomethine), ZnO, and poly(azomethine)/ZnO nanocomposites were prepared and characterized by Fourier transform-infrared spectroscopy, ultraviolet (UV)–visible spectroscopy, powder X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDAX), scanning electron Microscope (SEM), and transmission electron microscopy (TEM) techniques. Methylene blue (MB), Malachite green (MG), and Bismarck brown (BB) were degraded from water using poly(azomethine) (PAZ), zinc oxide (ZnO), PAZ/ZnO (PNZ) nanocomposites as photocatalyst in the presence of natural sunlight. The degradation efficiency and reaction kinetics were calculated, and the outcome of the photocatalytic experiments proved that the PAZ/ZnO nanocomposites reveals excellent photocatalytic activity and effective for decolorization of dye containing waste water than PAZ and ZnO in the presence of natural sunlight. The maximum degradation efficiency 97%, 96%, and 95% was obtained for PNZ nanocomposites at optimum dosage of catalyst as 500 mg and 50 ppm of MB, MG, and BB dye concentration, respectively. The maximum degradation time was 5 h. After photocatalytic study, the samples were characterized by Fourier-transform infrared spectroscopy (FT-IR) and UV–visible spectroscopy.

scholarly journals Simple Methylcadmium Alkoxides

2007 ◽  
Vol 62 (10) ◽  
pp. 1339-1342 ◽  
Author(s):  
Surajit Jana ◽  
Tania Pape ◽  
Norbert W. Mitzel
Keyword(s):  
Mass Spectrometry ◽  
Solid State ◽  
Molecular Formula ◽  
Equimolar Ratio ◽  
X Ray ◽  
X Ray Crystallography ◽  
Elemental Analyses ◽  
Solid State Structures ◽  
Structural Aspects ◽  
C Nmr

The reaction of dimethylcadmium with alcohols R-OH in equimolar ratio leads to the formation of tetrameric methylcadmium alkoxides with molecular formula [(MeCd)4 (OR)4] [R = Me (1), Et (2) and iPr (3)]. These compounds have been characterised by 1H, 13C NMR and IR spectroscopy, by mass spectrometry, elemental analyses and by X-ray crystallography (for 2 and 3). The solid state structures show distorted cubane-type aggregates with Cd4O4 cores. The structural aspects and the spectroscopic characterisations of these compounds are discussed.

scholarly journals Bio Synthesis and Characterization of Silver Nanoparticles Using Lagenaria siceraria Leaf Extract and their Antibacterial Activity

2014 ◽  
Vol 38 ◽  
pp. 35-45 ◽  
Author(s):  
B. Anandh ◽  
A. Muthuvel ◽  
M. Emayavaramban
Keyword(s):  
Silver Nanoparticles ◽  
Leaf Extract ◽  
Face Centered Cubic ◽  
Lagenaria Siceraria ◽  
Human Pathogens ◽  
X Ray Diffraction ◽  
Visible Spectroscopy ◽  
X Ray ◽  
Ft Ir ◽  
Uv Visible

The present investigation demonstrates the formation of silver nanoparticles by the reduction of the aqueous silver metal ions during exposure to the Lagenaria siceraria leaf extract. The synthesized AgNPs have characterized by UV-visible spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) techniques. AgNPs formation has screened by UV-visible spectroscopy through colour conversion due to surface plasma resonance band at 427 nm. X-ray diffraction (XRD) confirmed that the resulting AgNPs are highly crystalline and the structure is face centered cubic (fcc). FT-IR spectrum indicates the presence of different functional groups present in the biomolecules capping the nanoparticles. Further, inhibitory activity of AgNPs and leaf extract were tested against human pathogens like gram-pastive (Staphylococcus aureus, Bacillus subtilis), gram-negative (Escherichia coli and Pseudomonas aeruginosa). The results indicated that the AgNPs showed moderate inhibitory actions against human pathogens than Lagenaria siceraria leaf extract, demonstrating its antimicrobial value against pathogenic diseases

Structural studies of organoboron compounds. LVI. 1-Benzyl-7-methyl-3,5-diphenyl-2,4,6-trioxa-1-azonia-3-bora-5-boratabicyclo[3.3.0]octane and 1,4,6,9-tetramethyl-2,7-diphenyl-3,8,11,12-tetraoxa-1,6-diazonia-2,7-diboratatricyclo[5.3.1.12,6]dodecane

1992 ◽  
Vol 70 (11) ◽  
pp. 2809-2817 ◽  
Author(s):  
Wolfgang Kliegel ◽  
Gottfried Lubkowitz ◽  
Steven J. Rettig ◽  
James Trotter
Keyword(s):  
Solid State ◽  
Gas Phase ◽  
Phenylboronic Acid ◽  
Direct Methods ◽  
Structural Studies ◽  
Triclinic Space Group ◽  
Full Matrix ◽  
X Ray ◽  
Molar Ratios ◽  
New Type

The preparation of the N-(2-hydroxypropyl)-N-alkylhydroxylamines, 6a (R = CH3) and 6b (R = CH2Ph), and their reactions with phenylboronic acid are described. Regardless of the molar ratios of reactants employed, the reaction with 6b leads to the 1:2 condensate 1-benzyl-7-methyl-3,5-diphenyl-2,4,6-trioxa-1-azonia-3-bora-5-boratabicyclo[3.3.0]octane, 7, while that with 6a gives rise to the 1:1 condensate 1,4,6,9-tetramethyl-2,7-diphenyl-3,8,11,12-tetraoxa-1,6-diazonia-2,7-diboratatricyclo[5.3.1. 12,6]dodecane, 11 (the cyclic BONBON dimer of 4,6-dimethyl-2-phenyl-1,3-dioxa-4-aza-2-boracyclohexane, 9). Compounds 7 and 11 both crystallize in the triclinic space group [Formula: see text]: for 7; a = 13.126(1), b = 15.337(1), c = 10.9469(5) Å, α = 91.727(5), β = 104.647(5), γ = 72.922(7)°, Z = 4; and for 11; a = 9.0807(4), b = 9.1653(3), c = 6.4876(2) Å, α = 97.708(3), β = 108.830(3), γ = 89.188(4)°, Z = 1. The structures were solved by direct methods and were refined by full-matrix least-squares procedures to R = 0.038 and 0.032 for 5879 and 1827 reflections with I ≥ 3σ(F2), respectively. Compound 7 has the expected bicyclic pyroboronate structure, but represents the first reported N-substituted example of this type of compound. Bond lengths involving boron in 7 are (C) O—B(sp3) = 1.428(2) and 1.420(2), (B)O—B(sp3) = 1.472(2) and 1.468(2), N—B(sp3) = 1.737(2) and 1.762(2), C(phenyl)—B(sp3) = 1.588(2) and 1.584(2), (N)O—B(sp2) = 1.402(2) and 1.404(2), (B)O—B(sp2) = 1.331(2) and 1.329(2), C(phenyl)—B(sp2) = 1.555(3) and 1.553(2) Å. The X-ray analysis establishes a centrosymmetric, twofold N → B coordinated, dimeric structure in the solid state for 11 in which each B—O—N segment of a central six-membered BONBON ring is bridged by an O—C—C moiety. Compound 11 represents the first fully characterized example of a new type of "BONBON" compound. Bond distances involving the boron atom are (N)O—B = 1.465(1), (C)O—B = 1.428(1), N—B = 1.695(2), and C(phenyl)—B = 1.607(2) Å. Spectroscopic evidence indicates that in solution and in the gas phase this material exists predominantly as the monomer 9.

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