188032-51-1Relevant articles and documents
Oxidative Coupling of Carbazoles: A Substituent-Governed Regioselectivity Profile
Mallick, Sudesh,Maddala, Sudhakar,Kollimalayan, Kalidass,Venkatakrishnan, Parthasarathy
, p. 73 - 93 (2019)
Oxidative C-C coupling of carbazoles possessing various substituents is demonstrated in the presence of organic (metal-free) recyclable oxidants, such as DDQ or CA/H+, for accessing bicarbazole regioisomers. Differently substituted carbazoles are examined to showcase regioselective discrimination (3,3′-versus 1,3′-bicarbazoles) and preferences based on sterics and electronics in oxidative coupling. Finally, a mechanism that involves the carbazole radical cation has been traced (evidenced) and proposed on the basis of the UV-vis-NIR absorption and EPR spectroscopy results. This study underlines the strategic chemical preparation of a series of bicarbazoles in an efficient manner.