Wavenumbers of C=O valence vibrations of endo-bicyclo[2.2.1]hept-5-ene-2,3-dicarboximides

Abstract

Wavenumbers of symmetrical and antisymmetrical C=O valence vibrations of 50 derivatives of endo-bicyclo[2.2.1]hept-5-ene-2,3-dicarboximide have been measured in tetrachloromethane and chloroform. A satisfactory linear correlation between νs(C=O) and νas(C=O) has been found for 98 experimental points obtained in the two solvents. The anomalous low slope value ρ = 0.43 of this dependence can be used as evidence for endo configuration of the bicyclic 2,3-dicarboximides. The results are discussed in comparison with analogous relations found for other five-membered cyclic dicarboximides.