High Birefringent Bisdiynes and Hexatriynes Based on Double Elimination of (beta)-Substituted Sulfones

In order to realize high birefringence, acetylenes with long molecular size such as bis(phenyldiynyl)benzenes 1 and diphenylhexatriynes 4 are synthesized successfully on the basis of double elimination of the (beta)-substituted sulfones which can be prepared easily by reaction of benzyl or propargyl sulfones with propynal derivatives.