Synthesis of Novel Optically Active Poly(Amide-Imide)s with Benzophenone and L-Alanine Moieties.
3,3’,4,4’-Benzophenonetetracarboxylic dianhydride (4,4’-carbonyldiphthalic anhydride) 1 was reacted with L-alanine 2 in a mixture of acetic acid and pyridine (3:2) at room temperature, then was refluxed at 90–100 ?C and the resulting imide-acid 4 was obtained in quantitative yield. The compound 4 was converted to the diacid chloride 5 by reaction with thionyl chloride. The polymerization reaction of the imide-acid chloride 5 with benzidine 6a, 4,4’-diaminodiphenyl methane 6b, 1,5-diaminoanthraquinone 6c, 2,6- diamino pyridine 6d and 4,4’-sulfonyl dianiline 6e was carried out in DMAc solution in the presence of pyridine. The resulting poly(amide-imide)s were obtained in high yield and are optically active and thermally stable. All of the above compounds were fully characterized by IR spectroscopy, elemental analyses and specific rotation. Some structural characterization and physical properties of this optically active poly(amide- imide)s are reported.