Part I. Steric hindrance and the benzilic acid rearrangement. Part II. A study of anthracene dimer

Abstract

The benzilic acid rearrangement takes place with a yield greater than 90% for benzil itself and with lesser yields for substituted benzils, depending upon the kind and number of groups. In several cases where the substitute groups were in the ortho-positions to the carbonyl groups, the rearrangement proceeds with yields of 60% to 70%, for instance, o-tolil and mesityl phenyl diketone. nesitil was found to he hindered greatly enough that no detectable rearrangement takes place. The purpose of this work was to locate the point beyond which the rearrangement no longer takes place because of steric hindrance. The plan was to increase the hindrance gradually until the rearrangement was prevented; the reaction was carried out using three hindered diketones.