AN NMR-STUDY OF THE TAUTOMERISM OF 2-ACYLAMINOPYRIDINES

Application of the SIMPLE (secondary isotope multiplet NMR spectroscop y of partially labelled entities) technique to heteroaromatic tautomer ism proves that N-(pyridin-2-yl)acetamide 1 exists in [H-2]chloroform, [H-2(6)]acetone or [H-2(6)]benzene solutions as the amide tautomer-ro tamer A-I. The corresponding amide tautomeric form of N-(pyridin-2-yl) benzamide 2 was also found in [H-2]chloroform. These results confirm l ong-established patterns of heteroaromatic tautomerism, and illustrate the utility of SIMPLE in tautomerism studies.