Spectroscopic properties of some derivatives of camphor

Abstract

Aliphatic monocyclic imides have been reviewed by Hargreaves and his coworkers but few irnides have been investigated. Camphorimide was chosen in order to study the chiroptical and the spectroscopic properties of the imide chromophore. Camphorimide was prepared from camphoric acid. Some N-substituted aryl and aryl imides were also made, by opening the ring some amido-acids were prepared, Camphorquinone was condensed with 1,2-diamines to give camphorquinoxaline and substituted camphorquinoxalines. Dimethyluracil hydrate on condensation with camphorquinone gave pteridine dione. Camphorquinone-p-anisylinline was obtained when only one carbonyl group took part in the reaction with a monoamine. The infrared spectra of these compounds are discussed with particular reference to the N-H stretching and C=0 stretching vibrations as well as to the substitution pattern in aromatics. The proton nmr spectra revealed some interesting information regarding the shielding of the camphor group methyl protons.The uv and cd measurements have been found to be in reasonable agreement. Some of the uv bands are not found in the cd spectra,specially in the longer wavelength region.All the imides showed ord curves with a positive cotton effect. Owing to strong absorption it is not possible to take ord measurements for the quinoxalines below about 350nm. The pteridine dione and camphorquinone-p-anisylimine showed a high optical rotation in the near uv region.