FUROPYRIDINES .11. C-13 NMR-SPECTRA OF 2-SUBSTITUTED OR 3-SUBSTITUTED FURO[2,3-B]PYRIDINE, FURO[3,2-B]PYRIDINE, FURO[2,3-C]PYRIDINE AND FURO[3,2-C]PYRIDINE

The C-13 nmr spectra of 2- or 3-monosubstituted furo[2,3-b]- la-1j, furo[3,2-b]- 2a-2j, furo[2,3-c]- 3a-3j and furo[3,2-c]pyridine derivatives 4a-4j are reported. Effects by change in annelation and substituent effects on C-13 chemical shifts and carbon-proton coupling constants are discussed. The spectra of benzo[b]furan derivatives 5a-5j having the corresponding substituent are also reported for comparison.