A catalytic, high yielding and scalable procedure for the synthesis of 9H-carbazole-3,6-dicarbonitrile has been developed. Subsequent hydrolysis of the dinitrile in the presence of a catalytic copper species (i.e., CuI) yields 9H-carbazole-3,6-dicarboxylic acid. Both compounds are versatile and fine-tunable organic building blocks and therefore offer potential in material science, medicinal and supramolecular chemistry.