Chemical Methodologies
Volume:3 Issue: 5, Sep-Oct 2019

Three-component coupling of 2-naphthol, aldehydes, and urea has been accomplished in the presence of FeCl3 under microwave irradiation and solvent-free conditions to afford the corresponding synthesis of 1-phenyl-1, 2-dihydro-3H-naphtho[1,2-e][1,3]oxazin-3-onederivatives in excellent yields. It is a promising catalyst for the microwave-assisted reaction providing high product yield in a short period.

In this paper, we report the syntheses and crystal structuredetermination of three mononuclear and four-coordinated zinc(II) bromide complexes with chemical formula of [Zn(tsc)2]Br2 (1), Zn(PPh3)2Br2 (2) and Zn(Brcatsc)Br2 (3). The synthesized complexes are characterized by elemental analysis (CHN) and theircrystal structures are investigated by single crystal X-ray diffraction. In complex 1, the TSC coordinates to the zinc(II) ion as a bidentate ligand via N and S atoms. In complex 3, the thiosemicarbazone ligand Brcatsc coordinates to zinc(II) ion as a monodentate ligand via S atom. In these complexes, the zinc(II) ion coordinated in a distorted tetrahedral coordination geometry.

The organosulfur compounds are an important class of compounds with extensive pharmaceutical and synthetic concern as well as a prominent role in the living system. The development of effective methods for the introduction of sulfur atom into the carbon framework remains an eternal challenge, as most of the accounted process needs tenacious conditions. Owing to its economical and eco-friendly nature, eosin Y has emerged as a promising alternate to the transition metal catalyst in numerous organic transformations comprising C-H functionalization. The current work aims at a direct, efficient and single step synthetic route for the construction of thioethers, through oxidative coupling of the reaction partners facilitated by eosin Y as an organo photoredox catalyst.  The use of inexpensive and non-toxic dye, convenient reaction conditions, simple work-up procedure, and good to excellent yields are the advantages of this approach.

The main objective of this work is to study the sensivity of pristine, Al, P and Al & P doped Ga12N12 to adsorb phosgene (COCl2) molecule. The interaction of COCl2 from O, C and Cl sites on the surface of Ga12N12 is investigated by applying the density functional theory (DFT) at the cam-B3LYP/6-31G(d) level of theory. The geometrical and electrical structures, quantum descriptive, thermodynamic parameters, solvent effect, atom in molecule theory (AIM), natural bond orbital (NBO), and the reduced density gradient (RDG) are calculated at the above level of theory. The calculated results indicate that the adsorption of COCl2 on the surface of pristine and Al, P and Al & P doped Ga12N12 is exothermic, as well as Al-doped Ga12N12 is more favorable than P and Al & P doped. The recovery time results for adsorption of COCl2 from O site on the surface of Ga12N12, Al-Ga11N12, Ga12N11P and Al-Ga11N11P are 0.103, 4.69×10-7, 3.81×10-12 and 4.31×10-7 respectively. As a result, these nanoclusters can be used as sensor devices toward COCl2 molecule.The deformation energy results reveal that the structural change of Ga12N12 and COCl2 at all adsorption states are not significant. The AIM, RDG and NBO results demonstrate that the intermolecular interaction from O site of COCl2 on the surface of pristine, Al, P and Al & P doped Ga12N12 is stronger than C and Cl atoms sites of COCl2 as it is an electrostatic attractive type.The main objective of this work is to study the sensivity of pristine, Al, P and Al & P doped Ga12N12 to adsorb phosgene (COCl2) molecule. The interaction of COCl2 from O, C and Cl sites on the surface of Ga12N12 is investigated by applying the density functional theory (DFT) at the cam-B3LYP/6-31G(d) level of theory.  The geometrical and electrical structures, quantum descriptive, thermodynamic parameters, solvent effect, atom in molecule theory (AIM), natural bond orbital (NBO), and the reduced density gradient (RDG) are calculated at the above level of theory. The calculated results indicate that the adsorption of COCl2 on the surface of pristine and Al, P and Al & P doped Ga12N12 is exothermic, as well as Al-doped Ga12N12 is more favorable than P and Al & P doped. The recovery time results for adsorption of COCl2 from O site on the surface of Ga12N12, Al-Ga11N12, Ga12N11P and Al-Ga11N11P are 0.103, 4.69×10-7, 3.81×10-12 and 4.31×10-7 respectively. As a result, these nanoclusters can be used as sensor devices toward COCl2 molecule.

In the present paper, bovine serum albumin (BSA) was studied for extraction case from a buffer solution through a new version of modified magnetic chitosan nanocomposite.  Post-modification of this magnetic chitosan led to conversion of amine groups to dithiocarbamate on the surface of chitosan which was wrapped to superparamagnetic iron oxide nanoparticles (SPION). Chitosan was converted to magnetic chitosan over co-precipitation of Fe2+ and Fe3+ under alkali conditions. Amines of chitosan were also converted to dithiocarbamate over the reaction of carbon disulfide. Study of the synthesized support in BSA extraction was achieved in further experiments.

In this paper,nano-sized of mononuclear tetrahedral zinc(II) complex with the general formula of Zn((pma-ba)2en)Br2.2H2O, (pma-ba)2en=N,N¢-bis{(paramethylamino)benzylidene}ethylenediamine, was synthesized by ultrasonic bath assisted from the reaction of ZnBr2 and Schiff base ligand (pma-ba)2en in molar ratio 1:1 in methanol solution. The zinc(II) Schiff base complex characterized by elemental analyses (CHN), Fourier transformed infra-red (FT-IR) spectroscopy, X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). Also, thermal stability of the complex was studied from room temperature to 780 °C under argon atmosphere. TGA shows three stages for decomposition of the zinc(II) complex. At the end of decomposition, the remainder part is ZnO. The preparation of ZnO at the end of thermal decomposition confirmed with XRD. The XRD pattern of complex has shown that the sharp crystalline peaks indicating the crystalline phase in complex. By Scherrer’s formula, the average size of the nano-sizes of the complex was calculated >200 nm, that confirmed by SEM image. In addition, ZnO nanoparticles were obtained by thermal decomposition of zinc(II) Schiff base complex at 550 °C for 3 h. XRD result that the good crystallinity for zinc(II) oxide with no impurity observed in the ZnO product. The average size of the nanoparticles of the ZnO was calculated <50 nm.the formula is not displayed correctly!

A simple, rapid and dispersive liquid–liquid microextraction-solidification of floating organic drop procedure was combined with flame atomic absorption spectrometry and established for the determination of trace amounts of silver. 5-(4-dimethylamino-benzylidine) (Rhodenylene) ligand and 1-dodecanol were used as complexing agents and extracting solvents, respectively. The optimum extraction efficiency of silver was obtained after optimization of the pH, concentration of ligand, the nature and amount of solvent extraction, salt increase effect, extraction time, extraction temperature and stirring rate. The effects of various ions on the recovery of Ag were also investigated. The limit of detection defined as 3SB/m was 1.55 ngL−1. The sensitivity for three eight measurements of 10 and 100 μgL−1 of silver was 1.55 ngL−1. The relative standard deviation (RSD) for the measurements of 0.20 μgL−1 of silver was ±2.3%. Water well, mineral water and urban drinking water samples were analyzed for Ag amount. The microextraction method was satisfactorily used for the determination of Ag in various environmental waters.

In this work, a rapid and highly effectual protocol for the synthesis of bis-coumarins has been developed. The one-pot quasi three-component reaction of aromatic aldehydes (1 eq.) with 4-hydroxycoumarin (2 eq.) in the presence of catalytic amount of protic acidic ionic liquid triethylaminium-N-sulfonic acid tetrachloroaluminate (TSAT) under solvent-free conditions afforded the mentioned compounds in high yields and short reaction times.

The reactions of glycals with N-iodosuccinimide and acetic anhydride under solvent free conditions provide 2-deoxy-2-iodo-α-mannopyranosyl acetates with good stereoselectivity. The developed process is in accordance with principles of green chemistry and addresses the shortage of such methods for the regioselective iodo acetoxylation of alkenes.

This idea of this work included preparation new adhesive drug polymers to treatment the wounds and inflammations, new drug polymers were prepared as bio adhesive, which have high viscosity and treatment the wounds by the adhesion of both ends of the wound when it put as well as the speed of the treatment of external inflammation, because it remains inherent to the position of injury fast time, because of the property for it viscosity. A new bio adhesive polymer was prepared by modification of Pectin structure with acrylic acid (P1) as a spacer by using ceric ammonium nitrate (CAN) as an initiator, and new graft copolymer was substituted with amino drugs such as amoxicilli produced amide polymer. This design carries controlled delivery of therapeutic agents which could release the entrapped drug over an extended period of time due to its biodegradable, nontoxic and slow digesting nature. All prepared adhesive drug polymers were characterized by FTIR, 1H-NMR spectroscopes, thermo gravimetric analysis TGA and DSC were studied. intrinsic viscosities and physical properties of all prepared polymers were measured, biological activity was studied for all adhesive drug polymers  this new adhesive drug biological polymers were applied on different infected mice and wounds, It gave outstanding results and compliance mice infected with a full recovery by a short period of time.  The prepared drug copolymer was analyzed in different pH values at 37 °C in vitro study and controlled drug release was compared at zero time and after three days. The rate of hydrolysis in basic medium was found higher than acidic medium. It was concluded that modified drug release with extended drug action via slow release and in vivo performance was noted to be promising.