Use of Ionic Green Solvent for the Synthesis of Optically Active Aromatic Polyamides Containing a L-Leucine Moiety under Microwave Irradiation

A new series of spirothiazolidinone polymers has been accomplished by solution polycondensation of 4,12-dioxa-1,9-dithiadispiro[4.2.4.2]tetradecane-3,11-dione (3) with different aliphatic and aromatic diamines. A model compound 4 was prepared by the reaction of spiro-monomer 3 with benzyl amine and was characterized by elemental and spectral analyses. These polymers were characterized by elemental and spectral analyses. The thermal properties of these polymers were investigated by thermogravimetric analysis and differential thermal analysis measurements. The morphological properties of selected polymers 5c and 5e were tested using scanning electron microscope to study their surface morphology. The molar masses of polymers 5a, 5b, and 5d were determined by gel permeation chromatography. In addition, the anti-inflammatory activities were studied for these spiro-polymers in comparison with the model compound by determination in vivo using acute carrageenan-induced paw edema in rats.

Section: Tga Studymentioning

confidence: 99%

Synthesis and characterization of novel anti-inflammatory poly(spiro thiazolidinone)s

Abdelrahman

Hussein

2016

“…Ionic liquids (ILs) have recently generated a lot of interest in both academic and industrial investigations as environmentally benign alternatives to conventional organic solvents in an extensive range of processes owing interesting properties, such as outstanding microwave absorbance, wide liquid temperature range, designable structures, negligible volatility, elevated ionic conductivity, nonflammability, recyclability, good dissolving ability, and good thermal stability [32][33][34][35][36][37]. Besides, due to their low toxicity [38,39] and biodegradability [40], ILs are considered as potential substitute of environment friendly green solvent in sustainable process [41].…”

Section: Introductionmentioning

confidence: 99%

Novel heat resistant nanostructure poly(amide–imide)s containing new TMA-based diacid via conventional polycondensation reaction in an ionic green medium: synthesis, morphology, and thermal properties

Mallakpour

Zeraatpisheh

2012

Self Cite

The 4,4′-Methylenebis(3-chloro-2,6-diethylaniline) has been reacted with two moles of trimellitic anhydride in refluxing N,N′-dimethylformamide to obtain 4,4′-Methylenebis(3-chloro-2,6-diethyl trimellitimidobenzene) for the first time. A series of novel poly(amide-imide)s (PAIs) was synthesized by the direct polycondensation of the synthesized diimidediacid with various commercial diamines. The direct polyamidation was performed under conventional heating reaction using tetra-n-butylammonium bromide and triphenyl phosphite as a condensing agent. The PAIs were obtained in good yields and moderate inherent viscosity up to 0.48 dL/g. Although the polymers were not soluble in low polar solvents tested, they were thoroughly dissolved in high polar solvents and even in a moderate polar solvent such as pyridine. The crystallinity of the prepared PAIs was measured by XRD scans. No remarkable crystal diffraction was detected for the polymers obtained, and they showed almost an amorphous diffraction patterns. The thermal behavior of the polymers was evaluated by thermogravimetric analysis (TGA) technique. This study showed obviously one-stage decomposition at elevated temperatures. On the basis of TGA data, such polymers are thermally stable and can be classified as self-extinguishing polymers. The structural features of these polymers were verified by elemental analysis, fourier transform infrared spectroscopy, and 1 H-NMR spectroscopies. The field emission scanning electron microscopy (FE-SEM) micrographs showed the obtained PAIs have nanostructure morphology. The effect of ultrasonic irradiation on the polymer morphology was studied. The FE-SEM micrographs illustrated that the morphology of macromolecules after ultrasonication became more homogenous than it is before ultrasonic radiation.

“…One of the most practical and widely accepted applications of chiral macromolecules is the use as chiral stationary phase (CSP) for high-performance liquid chromatography (HPLC) for the separation of racemic compounds (resolution). There are three types of chiral polymers used as CSP: biopolymers, polymers prepared by modification of naturally occurring polymer backbones such as polysaccharides and those having a fully synthetic structure [27][28][29][30][31][32][33].…”

Section: Introductionmentioning

confidence: 99%

“…The unique structures and the potential applications of these polymers have attracted researchers to develop various polymerization techniques. Owing to the importance of the green route for the synthesis of chiral extended polymers, in prolongation of our research [28][29][30][31][32][33], herein, we wish to describe a successful use of N -trimellitylimido-S-valine (1) to prepare optically active PAIs by the direct polycondensation with different diisocyanate using TBuAmBr an efficient, safe and environmentally benign green route by different catalysts. These results were compared with previous work with conventional solvents [34].…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Characterization of Poly(Amide-Imide)s Bearing a S-Valine Moiety in Molten Ionic Liquid

Mallakpour

Khania

2011

Self Cite

A study has been conducted to synthesize highly organosoluble and optically active poly(amide-imide)s via direct solution polycondensation of different aliphatic and aromatic diisocyanates with a chiral diacid monomer in the presence of molten tetrabutylammonium bromide (TBuAmBr) as a molten ionic liquid, and was compared with polymerization in traditional solvents like N-methyl-2-pyrrolidone (NMP). The step-growth polymerization of N-trimellitylimido-S-valine (1) as an optically active monomer with 4,4 -methylenebis(phenyl isocyanate) (MDI) (2a) was carried out by four different methods in the presence of pyridine (Py), dibutyltin dilaurate (DBTDL), triethylamine (TEA) as a catalyst and without catalyst, respectively. In these solutions polycondensations amino acid was used as chiral inducing agent. The optimized method of MDI (2a) was used for the polymerization of hexamethylene diisocyanate (HDI) (2b), isophorone diisocyanate (IPDI) (2c) and tolylene-2,4-diisocyanate (TDI) (2d). The resulting polymers have inherent viscosities in the range of 0.15-0.87 dl/g and were characterized with FT-IR, 1 H-NMR, elemental and thermogravimetric analysis techniques. In comparison with conventional solvents, this approach exhibited smoothly higher inherent viscosities and comparative yields and thermal stability. This process is safe and green since toxic and volatile organic solvents such as NMP were eliminated. These polymers are optically active, thermally stable and soluble in amide-type solvents.