The Interaction Vector Model and the Secondary Transition of Diphenylether, and of Some of Its Natural Derivatives: Enneaphylline, Pilocereine, Chondrocurine, Daphnandrine, Daphnoline, Tiliacorine

Abstract

Using the interaction vector model^1,2 (IVM), it is possible to calculate the intensity of the secondary transition of the benzene chromophore (towards 255 nm for the benzene molecule itself), on a very simple basis. This transition is electronically forbidden because of the D_6h symmetry of the benzene molecule. Many spectra have been studied with the IVM, specially those of natural products since they are the main concern of the laboratory. Alkyl, amino, hydroxy, alkoxy substituents, fused rings effects have been taken into account. The present work will be devoted to the study of diphenylether (φ-O-φ) derivatives which display an interesting challenge to the IVM since the two phenyl rings are “conjugated” through the oxygen non bonding electrons.