Highly Selective Electrosynthesis of Biphenols on Graphite Electrodes in Fluorinated Media

• Published in: Chemistry : a European journal Vol. 17; no. 50; pp. 14164 - 14169
• Main Authors: Kirste, Axel, Hayashi, Shotaro, Schnakenburg, Gregor, Malkowsky, Itamar M., Stecker, Florian, Fischer, Andreas, Fuchigami, Toshio, Waldvogel, Siegfried R.
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 09.12.2011; WILEY‐VCH Verlag; Wiley; Wiley Subscription Services, Inc
• Subjects: Anodic; Chemical reactions; Chemistry; Chemistry, Multidisciplinary; CC coupling; Diamonds; electrochemistry; Electrodes; fluorinated compounds; Fluorination; Graphite; Joining; oxidation; Phenol; Phenols; Physical Sciences; Science & Technology; C-C coupling; ASYMMETRIC CATALYSIS; phenols; electrochemistry; ENANTIOSELECTIVE SYNTHESIS; oxidation; ETHERS; SOLVENTS; COUPLING REACTION; SCIENCE; fluorinated compounds; METATHESIS; ANODIC-OXIDATION; CONJUGATE ADDITION
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201102182

The direct and selective phenol coupling reaction that provides biphenols still represents a challenge in organic synthesis. The recently developed electrosynthesis on boron‐doped diamond anodes with fluorinated additives was developed further to allow the application to less‐expensive electrodes and fluorinated media. This advanced protocol allows the highly selective anodic phenol coupling reaction on graphite with a broad scope. Good old graphite: Commonly available and inexpensive graphite electrodes combined with fluorinated additives allow a similar reaction profile in the anodic phenol coupling as observed at boron‐doped diamond electrodes. Some substrates are even more efficiently coupled than at the diamond anodes. With this method a variety of electron‐rich and halogenated biphenols have been formed exclusively (see scheme).