The synthesis of 3,3,4,4-tetraphenyl-2-butanone from 1,1-diphenylacetone

The preparation of 3,3,4,4-tetraphenyl-2-butanone by treatment of 1,1-diphenylacetone(1,1-DPA) with potassium-t-butoxide or lithium diisopropyl amide in THF at 0°C followed by heating with a diphenylmethylhalide is described. A single crystal X-ray analysis on the new ketone shows that the molecule crystallizes in a conformation in which the carbonyl group is not eclipsed with the benzylic hydrogen, but has a torsional angle of +41° toward a gauche (120°) conformation.