Addition of triethylaluminum to diphenylacetylene

Summary

• 1. Triethylaluminum and diphenylacetylene react at 110–120° with formation of 1, 2-diphenyl-1-butene, two geometric isomers of l, 2, 3, 4-tetraphenyl-1,3-hexadiene of m. p. 91–92° and 129–130°, and a little 1,2,3,4-tetrapheny 1−1,3-butadiene.

• 2. On the basis of the infrared absorption spectra the liquid 1,2-diphenyl-1-butene was assigned the cis configuration and the solid isomer the trans configuration.