INTERMOLECULAR AND INTRAMOLECULAR HYDROGEN-BONDING IN 5-PYRIDYLMETHYLENEHYDANTOINS - IR AND NMR-STUDY

The patterns of the NH stretching vibrations in the solid-state IR spectra of a series of 5-pyridylmethylenehydantoins revealed the presence of various modes of hydrogen bonding: intermolecular NH....OC and intermolecular or intramolecular NH....N(py). These variations are related to the orientation of the pyridyl nitrogen and to stereochemistry. A distinction between intramolecularly and intermolecularly hydrogen-bonded compounds was also provided by comparison of the H-1 NMR spectra in (CD3)2SO and in CDCl3.