A Novel Three-Step Synthesis of N-(2-Ethylhexyl)-2,7-diiodocarbazole

Abstract

A new short and reasonably efficient synthesis of N-(2-ethylhexyl)-2,7-diiodocarbazole is presented. 4,4′-Diiodobiphenyl was nitrated and the resulting 4,4′-diiodo-2-nitrobiphenyl was converted via Freeman’s modification of the Cadogan ring closure into 2,7-diiodocarbazole, which was then alkylated in the final step. The synthesis represents a significant simplification of the reported five-step procedure.

Key words

carbazole ring closure - electrophilic aromatic substitution - heterocycles - polymers - conjugation

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