Part A. Accelerated curing of aryl-ethynyl end-capped polyimides. Part B. Catalytic pockets assembled by ion-pairing

Part A. A series of end-cap model compounds were synthesized to determine the effect of modification of the aryl-ethynyl end-cap on the thermal curing process. Using 1H NMR and SEC, an accelerated thermal cure was discovered by replacement of the terminal phenyl group with 1-naphthyl- and 9-anthracenyl-ethynyl moiety. The acceleration (phenyl < naphthyl < anthracenyl) is in direct contrast to the steric bulk about the ethynyl bond (phenyl < naphthyl < anthracenyl). The acceleration discovered between phenyl- and naphthyl-model compounds occurs without a decrease in E_a, suggesting a difference in parameter(s) accounted for in A as the source of the acceleration. The thermal curing products of all model compounds are of approximately dimeric/trimeric structure with no higher products formed even towards complete reaction. The insoluble 2-naphthyl-analogue and the phenyl-control were studied using FTIR. The 2-naphthyl-model compound cures slightly faster, but with higher E_a, than the control phenyl-analogue. The analogous naphthyl- and anthracenyl-end-capped oligomers were synthesized and studied using DSC. The rate acceleration is also observed for the oligomers, resulting in a fast curing material. Analysis of the crystal structure and molecular mechanics of the model compounds reveals no significant differences in bond lengths or dipole moments, but a calculation of hyperpolarizability reveals an increase in the same order of the thermal cure trend (phenyl < naphthyl < anthracenyl). Incorporation of additional ether linkages in the backbone significantly effects the properties of the oligomers and resulting resins, but the rate acceleration using aryl-ethynyl end-caps are still observed and relatively unaffected by the backbone. Aryl-ethynyl model compounds incorporating electronic substituents were studied using SEC. An additional rate acceleration is observed by the incorporation of an electron-donating methoxy-substituent para to the ethynyl unit. The electron-withdrawing cyano-substituent has no effect. The analogous methoxy-naphthyl-ethynyl end-capped oligomer cure fits second-order kinetics best, unlike all other model compounds and oligomers studied, which demonstrate first-order kinetics. POSS monomers were incorporated into aryl-ethynyl end-capped oligomers and verified by NMR and SEC, and the resulting oligomers were found to undergo thermal cure to afford a new inorganic/organic hybrid resin. The new resins are also easily modified for fast-curing kinetics by incorporation of the new, fast-curing aryl-ethynyl end-caps.; Part B. Improved synthetic methods were used in the synthesis of 2,9-bis(aryl)- and 2,9-bis(arylethynyl)-1,10-phenanthroline ligands, including an unsymmetrical ligand. Further synthesis results in dianionic ligands for use in ion-pairing. The palladium complexes of 2,9-bis(aryl)- and 2,9-bis(arylethynyl)-1,10-phenanthroline ligands suffer from a cyclometallation reaction and a coordination shift, respectively, resulting in unsymmetrical complexes. The rhodium complexes of 2,9-bis(arylethynyl)-1,10-phenanthroline however, were found to be incredibly soluble and symmetric. Solution ion-pairing through proton transfer was accomplished and verified using 1H NMR. No enhanced optical rotations were observed between the 1:1 ion-pair and a 2:1 ion-pair control. A copper (I) complex was synthesized from the ion-paired ligand and confirmed by UV-visible spectroscopy and elemental analysis. Neutral and dicationic polymer-supported diamines were synthesized and the latter used in the formation of an ion-pair through ion-exchange. The polymer-supported ion-paired ligand was confirmed using FTIR. A resulting rhodium complex was also confirmed by FTIR and demonstrated catalytic activity in a benchmark hydrogenation reaction, in which the catalytic activity is intimately involved with the polymer-support.