COMPLETE ASSIGNMENT OF THE H-1 AND C-13 NMR-SPECTRA OF 11,12-DIMETHOXY[1]BENZOTHIENO[3,2-A]-4,7-PHENANTHROLINE AND ITS 8-CHLORO ANALOG - CONCERTED USE OF 2-DIMENSIONAL NMR TECHNIQUES

The H-1 and C-13 nmr spectra of 11,12-dimethoxy[1]benzothieno[3,2-a]-4,7-phenanthroline and its 8-chloro precursor were totally assigned using a combination of two-dimensional nmr techniques. After correlation of the majority of the proton signals by a COSY spectrum and one-bond heteronuclear correlation, the full assignment of the H-1 and C-13 nmr spectra of the novel heterocyclic compounds required the application of long-range CH coupling information particularly for quaternary carbon resonance assignments and the orientations of individual spin systems relative to one another. Key long-range heteronuclear couplings in both compounds served to confirm the one-bond heteronuclear correlations. Unequivocal interpretation of the spectral data leads to the complete assignments of the resonances.