An infrared study of ‐conco‐ structures

Abstract
The infrared carbonyl frequencies of a variety of hydantoins were collected. It was found that the high frequency band can be attributed to the CO group in the 2‐position. Acylation of the 1‐N or 3‐N atom probably effects a rehybridization of the N atom by which the s character of the adjacent CO bonds is increased.