91539-41-2Relevant articles and documents
Circular Dichroism of Some N-Monosubstituted and N,N-Disubstituted Benzamides
Ringdahl, Bjoern
, p. 141 - 152 (2007/10/02)
The circular dichroism (CD) spectra of some N-benzoyl-1-alkyl-2-propynylamines and N-benzoyl-1-alkyl-2-propenylamines show three Cotton effects (CE's) in the near ultraviolet region.These are assigned to 1Lb, n->?* and 1La transitions of the N-monosubstituted benzamide chromophore.The 1Lb and n->?* CE's are negative and positive, respectively, for the R configuration.In the N-benzoyl-1-alkyl-2-propenylamines, the 1La CE's appear to be developed primarily through dipole - dipole coupling between allowed (?-?*) transitions of the benzamide chromophore and the ethenyl group.The benzoyl derivatives of some 2- and 3-substituted pyrrolidines also exhibit three CE's which are assigned to 1Lb n->?* and 1La transitions of the N,N-substituted benzamide chromophore.In benzoyl derivatives of 2-substituted pyrrolidines, these CE's are negative, positive and negative, respectively, for the D-proline configuration.The effect of increasing nonplanarity of the phenyl and amide groups, brought about by ortho-methyl substitution, on the CD behaviour of both N-monosubstituted and N,N-disubstituted benzamides is discussed.
