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Aryldiazonium silica sulfates were employed as new and efficient reagents for Heck-type arylation reactions with styrene and methyl acrylate. The reactions were carried out in an organic solvent, in the presence of Pd(OAc) 2 as precatalyst without use of base and free ligand. The trans isomers of desired products, methyl cinnamates and stilbenes, were obtained with full conversion. Use of a catalytic amount of Pd(OAc) 2 produced the corresponding products in short reaction times and excellent yields.

In the presented study, 3,5-diamino-N-(4-methyl-1-oxo-1-(phenylamino)pentan-2-yl)benzamide (V) as a new diamine monomer is synthesized and fully characterized by means of FT-IR, 1 H-NMR, 13 C-NMR, and elemental analysis techniques. The stated diamine is used for the sol-gel fabrication of a series of polyimide (PI)/titania nanohybrid films with various titania percentages. The special design of diamine monomer containing bulky pendant group increased the flexibility of resulted PI matrixes. On the other hand, the ability to construct strong organic/inorganic Hbond lattice has led to the effective surrounding of nanoparticles by PI grounds and thus the well-dispersed quite spherical nanoparticles were created via a sol-gel procedure. The obtained nanocomposites showed high thermal stability and UV-vis absorption efficiency. The X-ray diffraction experiments confirmed the titania nanoparticles to be amorphous.

5-(4-Methylthio-2-phthalimidylbutanoylamino)isophthalic acid (5) as a novel diacid monomer containing phthalimide and flexible chiral groups was prepared by dehydration of L: -methionine and phthalic anhydride followed by reacting with thionyl chloride and then treating with 5-aminoisophthalic acid (5AIPA) in dry N,N-dimethylacetamide (DMAc). A series of novel polyesters (PEs) containing phthalimide group was prepared by the reaction of diacid monomer 5 with several aromatic diols via direct polyesterification with tosyl chloride/pyridine/dimethylformamide (DMF) system as condensing agent. The resulting new polymers were obtained in good yields and inherent viscosities ranging between 0.21 and 0.51 dLg(-1) were characterized with FT-IR, 1H NMR, elemental and thermogravimetric analysis techniques. These polymers are readily soluble in polar organic solvents such as DMAc, DMF, dimethyl sulfoxide and protic solvents such as sulfuric acid. Specific rotation experiments demonstrate the optical activity induction due to successful insertion of L-methionine in the structure of pendent groups. Thermogravimetric analysis showed that the 10% weight loss temperature in a nitrogen atmosphere were more than 315 degrees C, which indicates that the resulting PEs have good thermal stability.

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A variety of wholly aromatic organosoluble optically active polyamides (PAs) have been synthesized through polycondensation of a chiral diacid monomer and several aromatic diamines under microwave irradiation conditions. Polycondensations proceded in both ionic liquid and conventional organic solvent and compared results proved that ionic liquid in conjunction with triphenyl phosphite under microwave irradiation represented an advanced polyamidation agent from both environmental and economical viewpoints as well as improvement of reaction times and yields and the viscosities of final polymers. Furthermore, the Lmethionine-containing bulky monomer induced the optical activity into the polymer chains and perfected the organosolubility of PAs with preservation of their thermal resistances simultaneously. Synthesized PAs were characterized by FT-IR, specific rotation measurements, elemental analysis and 1 H-NMR techniques. Thermal stability of the resulting PAs was evaluated by thermogravimetric analysis and differential scanning calorimetry.

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