A double elimination protocol has been established for access to unsymmetrically substituted aromatic polyynes by use of dialdehyde and substituted benzylic or propargylic sulfones as starting compounds. For this protocol, various substituted sulfones and phthalaldehydes were usable giving rise to the formation of the desired substituted aromatic polyynes. (C) 2003 Elsevier Ltd. All rights reserved.
High Birefringent Bisdiynes and Hexatriynes Based on Double Elimination of β-Substituted Sulfones
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 β-substituted sulfones which can be prepared easily by reaction of benzyl or propargyl sulfones with propynal derivatives.