Relations between Electronic Absorption Spectra and Spatial Configurations of Conjugated Systems. III. o,o′-Bridged Biphenyls

The ultraviolet absorption spectra of some o,o′-bridged biphenyls and their relations to the spatial configurations have been discussed. The method developed in the earlier parts of this series has been applied to these compounds, especially o,o′-three-atom-bridged (o,o′-7-memberedring-bridged) and o,o′-four-atom-bridged (o,o′-8-membered-ring-bridged) biphenyls, and the interplanar angles have been calculated to be about 44.5∼47.3° (average, 46°) for the former compounds and about 58.0∼61.5° (average, 59.8°) for the latter.