N-trimellitylimido-L-methionine (3) was prepared by reaction of trimellitic anhydride (1) with -L-methionine (2) in acetic acid solution at refluxing temperature. This diacid was reacted with thionyl chloride, and N-trimellitylimido-L-methionine diacid chloride (4) was obtained in quantitative yield. The resulting diacid chloride was reacted with p-aminobenzoic acid in dry acetone and bis(p-aminobenzoic acid)-N-trimellitylimido-L-methionine (5) was obtained as a novel optically active amide-imide diacid monomer in high yield. The direct polycondensation of amide-imide diacid monomer 5 with several aromatic diamines was carried out with tosyl chloride (TsCl)/pyridine (Py)/dimetheylformamide (DMF) system. The resulting thermally stable poly(amideimide)s (PAIs) were obtained in good yields and inherent viscosities ranging between 0.24 and 0.46 dL g À1 and were characterized with FTIR, 1 H NMR, CHN, and TGA techniques.

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N-Trimellitylimido-S-valine (3) was prepared by reaction of trimellitic anhydride (1) with S-valine (2) in acetic acid solution at refluxing temperature. This diacid was reacted with thionyl chloride and N-trimellitylimido-S-valine diacid chloride (4) was obtained in quantitative yield. The reaction of this diacid chloride with p-aminobenzoic acid was carried out in dry tetrahydrofurane and bis(paminobenzoic acid)-N-trimellitylimido-S-valine (5) was obtained as a novel optically active amide-imide diacid monomer in high yield. The direct poly condensation of amide-imide diacid monomer with aromatic diamins such as 4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl ether, benzidine, 4,4'-diaminodiphenyl methane, 1,4- phenylene diamine and 2,5-diamino toluene was carried out in tosyl chloride/ pyridine/dimethylformamide system. The resulting novel optically active poly(amide-imide)s (PAIs) with inherent viscosities ranging from 0.24-0.76 dLg-1, were obtained in good yield. All of these polymers were fully characterized with FTIR spectroscopy and specific rotation. Some elemental analysis, thermal properties and 1H-NMR of these new optically active PAIs are also reported.

In this paper poly (4-methyl vinylpyridinium hydroxide)/SBA-15 composite was prepared as a highly efficient heterogeneous basic catalyst by in situ polymerization method for the first time. It was characterized by XRD, FT-IR, BET, TGA, SEM and back titration using NaOH. This catalyst exhibited the excellent catalytic activities for the Knoevenagel condensation of various aldehydes with ethyl cyanoacetate. Over this catalyst, α,β-unsaturated carbonyl compounds were obtained in the reasonable yield at 95 o C in 10 -30 min in H2O as a solvent with a 100% selectivity to the condensation products. Catalyst could be easily recycled after the reaction and it could be reused without the significant loss of activity/selectivity performance. No by-product formation, high yields, short reaction times, mild reaction conditions and operational simplicity with reusability of the catalyst were the salient features of the present synthetic protocol. Presence of H2O as a solvent was also recognized as a "green method".

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Amino functionalized triazine supported on silica-gel was prepared and characterized. This new triazine derivative was applied as a coordinating agent for aluminum chloride. This novel Lewis acid supported on heterogeneous surface was used as an effective catalyst for protection of alcohols and phenols in the presence of 3,4-dihydro-2H-pyran. This catalyst can be reused without any significant loss of activity, and it protects alcohols in the presence of phenols.

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