Synthesis and characterization of precursors of ladder polymers

Abstract

The synthesis of new soluble hemiporphyrazinato-nickel-complexes 1 as bisdienophiles for Diels-Alder-polymerisation is described. By variation of position and type of the substituents attached to ':he hemiporphyrazine system soluble monomers were obtained. The compounds were characterized by IH-, 13C-NMR and m a s s spectroscopy. Reacting these bisdienophiles with dienes yielded bisadducts as model compounds. Dimers and oligomers of the hemiporphyrazines could be obtained by repetitive Diels-Alder reaction with suitabl'e bisdienes like cyclic tetraenes 2. The oligomers were studied by NMR-and mass spectroscopy. R R R' --0--c=c-New n-type conducting poly(arylene)s, poly(quinoline-2,6-diyl) (P(2,6-Q)), poly(quinoxaline-2,6diyl) (P(2,6-Qx)), and poly( 1,5-naphthyridine-2,6-diyl) (P(2,6-N)), were synthesized by using nickel complex. n X-Ar-X + n NI(0)Lm --( A r k + NiX2LmThese polymers have 2,6-naphthylene-like units with imine nitrogen(s) and have more extended xconjugation system as well as higher electron-accepting properties than their isomeric poly(quino1me-W d i y l ) and poly(quinoxline-5,8-diyl), revealing that the 2,6-naphthylene-like bonding between the monomer units is especially suitable for the extensive n-conjugation. 302