Twofold Electrochemical Amination of Naphthalene and Related Arenes

The twofold, electrochemical amination reaction of polycyclic arenes, e.g. naphthalene (4), via Zincke intermediates is demonstrated for the first time. The installation of the nitrogen functionalities occurs regioselectively in positions 1 and 5 of naphthalene (4). The key for this electro-conversion is boron-doped diamond as anode material. The method of the multi-amination reaction is expanded to other aromatic substrates. A detailed study is provided, covering electrolysis parameters, e.g. anode material, electrolyte system, current density, separator, etc. Despite the moderate yields, this approach offers the first direct electro-synthetic access to diaminated products.

Electrochemical Amination of Less-Activated Alkylated Arenes Using Boron-Doped Diamond Anodes

The anodic C–H amination of aromatic compounds is a powerful and versatile method for the synthesis of aniline derivatives. By using boron-doped diamond (BDD) anodes, a method initially described by Yoshida et al. for electron-rich arenes was expanded to less-activated aromatic systems e.g., simple alkylated benzene derivatives. Anodes based on sp3 carbon seem to be the key for the electrochemical amination reaction. The corresponding primary anilines are obtained in good yields. Despite the cationic intermediates of the electrolytic reaction tert-butyl moieties are tolerated.

ChemInform Abstract: Electrochemical Amination of Less-Activated Alkylated Arenes Using Boron-Doped Diamond Anodes.

CCDC 1545585: Experimental Crystal Structure Determination

Related Article: Sabine Möhle, Sebastian Herold, Frank Richter, Hartmut Nefzger, Siegfried R. Waldvogel|2017|ChemElectroChem|4|2196|doi:10.1002/celc.201700476