COMPARATIVE 2-DIMENSIONAL NMR ANALYSIS OF POLY(N-BUTYL-3,6-CARBAZOLYLENE), POLY(N-VINYLCARBAZOLE) AND MODEL COMPOUNDS

The two-dimensional NMR spectrum of poly(N-butyl-3,6-carbazolylene), prepared by electro-chemical synthesis, is presented and assigned on the basis of correlations between directly bonded carbons and protons and of those obtained for N-butyl-3,6-dibromocarbazolylene as a model compound. The isolated aromatic protons (numbers 4, 5) were found to be less shielded than their bonded carbons, because of the magnetic influence of the next-neighbour substitutents. The 2D-NMR spectrum of commercial poly(N-vinylcarbazole) was reinvestigated and assigned from both the edited spectrum, the 2D-NMR of N-ethylcarbazole as a model compound and assignments made for 3,6 substituted carbazolylenes. From all the results, complete assignments of the aromatic region were made. Complete splitting of both the carbons and protons was found, owing to the non-equivalence of the two benzene rings fused to the pyrrole ring.