Synthesis of differentially substituted hexaethynylbenzenes based on tandem Sonogashira and Negishi cross-coupling reactions

[GRAPHICS] Synthesis of polyethynyl-substituted aromatic compounds was achieved effici ently by the use of the Negishi cross-coupling reaction, and this method, c oupled with the Sonogashira reaction, was applied to the synthesis of diffe rentially substituted hexaethynylbenzenes from chloroiodohenzenes.