Synthesis of 1,3-Bis(tetracyano-2-Azulenyl-3-Butadienyl)azulenes by the [2+2] Cycloaddition-Retroelectrocyclization of 1,3-Bis(azulenylethynyl)azulenes With Tetracyanoethylene

Chemistry - A European Journal - United Kingdom
doi 10.1002/chem.201402939