A series of tetracyclones has been synthesized in order to study absorption spectra. Substituents were introduced singly, in pairs and in quadruplet in the p-position of the phenyl rings. The syntheses of a number of substituted benzoins, benzils and 1, 3-diphenyl- Z-propanones are described as well as tetraphenylphthalic anhydrides which are derivatives for the tetracyclones. Previous observations were conwed in that p- ...