New organic polymers, I. Synthesis and characterization of poly Schiff bases from benzidine‐3,3′‐dicarboxylic acid

Abstract

Thermally stable and semiconducting polymers are synthesized by condensing benzidine-3,3 '-dicarboxylic acid (BDC), with dicarbonyl compounds like glyoxal, cyclohexane-1,4-dione, 4,4'-diacetyl diphenyl ether and benzil under different experimental conditions. These poly Schiff bases are insoluble in common organic solvents. They are characterized by IR-and viscosity studies, thermal analysis, and the study of electrical properties at various temperatures. Variation of the electrical conductivity, o, with temperature was found to confirm with the empirical relation: = oo . e-E/kT ZUSAMMENFASSUNG:Thermisch bestiindige und halbleitende Polymere wurden durch Kondensation von Benzidin-3.3 'dicarbondure mit Dicarbonylverbindungen wie Glyoxal, Cyclohexan-1,4dion, 4,4 '-Diacetyldiphenylether und Benzil bei unterschiedlichen experimentellen Bedingungen hergestellt. Diese Poly-Schiff-Basen sind in herkOmmlichen organischen LOsungsmitteln unlOslich. Sie wurden mittels IR-und Viskositltsuntersuchungen, thermischer Analyse und Untersuchung der elektrischen Eigenschaften bei verschiedenen Temperaturen charakterisiert. Die Temperaturabhiingigkeit der elektrischen Leitfiihigkeit o ergab eine Bestatigung der empirischen Beziehung:

Polymeric Copper(II) Complexes with a Newly Synthesized Biphenyldicarboxylic Acid Schiff Base Ligand—Synthesis, Structural and Thermal Characterization

“…Both carboxylic groups only slightly deviate from the mean plane through the phenyl cores, which is indicated by the dihedral angles between the planes through the atoms of the phenyl ring C1-C2-C3-C4-C5-C6, i.e., C1 -C2 -C3 -C4 -C5 -C6 and atoms of the carboxyl group O1-C7-O2-C4, i.e., O1 -C7 -O2 -C4 , which are 6.20(16) • and 5.90 (19) • , respectively. The same conclusion is reached if the torsion angles C3-C4-C7-O2 and C5 -C4 -C7 -O2 are considered, the values of which are 5.7(4) • , and 4.1(3) • , respectively.…”

“…However, Schiff bases of [1,1 -biphenyl]-3,3 -dicarboxylic acid with 4-(1,2,2-triphenylethenyl)-benzaldehyde and 2-hydroxy-1-naphthaldehyde were patented as Diazomethine pigment dyes [18]. In addition, several polymeric Schiff bases of amino-[1,1 -biphenyl]-3,3 -dicarboxylic acid were synthesized [19]. There are limited reports of coordination compounds that include these compounds as ligands.…”