9504. Tolan

Nomenclature

CAS number: 501-65-5
1,1′-(1,2-Ethynediyl)bisbenzene; diphenylacetylene; diphenylethyne.
C14H10; mol wt 178.23.
C 94.34%, H 5.66%.

Description and references

Prepd by the oxidation of benzil dihydrazone with mercuric oxide: Schlenk, Bergmann, Ann. 463, 76 (1928); by dehydrohalogenation of stilbene dibromide: Sderbck, Ann. 443, 161 (1925); Smith, Hoehn, J. Am. Chem. Soc. 63, 1180 (1941); Smith, Falkof, Org. Synth. coll. vol. III, 350 (1955). Improved procedure: L. F. Fieser, Experiments in Organic Chemistry (Boston, 3rd ed., 1955) p 181.

Chemical structure

Properties

Monoclinic, pseudo-rhombic rods or large spears from 95% ethanol. mp 60-61° (also reported as 62.5°). bp760 300°; bp19 170°. Dipole moment 0.3. Specific heat at 20°: 0.297. uv max: 216, 221, 269, 272, 279, 288, 297 nm (ε 20600, 20300, 23450, 25200, 33000, 23250, 29400). Insol in water. Freely sol in ether, hot alcohol.