Ruthenium‐Catalyzed Cross‐Dehydrogenativeortho‐N‐Carbazolation of Diarylamines: Versatile Access to Unsymmetrical Diamines

Abstract

The dehydrogenative C-N cross-coupling of unprotected, secondary anilines through ortho-N-carbazolation has been achieved using a Ru catalytic system with O2 as the terminal oxidant. The reactions proceed in an intermolecular fashion, selectively in the ortho position. Implications for the field of organic synthesis are discussed.

Catalyst‐ and Reagent‐Free Electrochemical Azole C−H Amination

“…The synthetic utility of the catalyst‐free, electro‐oxidative C−H amination was highlighted by the efficient synthesis of coumarin 4 , which was shown to display highly potent anti‐HIV and anti‐tumor activities . The desired product 4 was hence obtained from commercial substrates under metal‐free conditions (Scheme ), which obviates residual trace metal removal for drug syntheses by the practitioner.…”

Direct Synthesis of N-H Carbazoles via Iridium(III)-Catalyzed Intramolecular C–H Amination

“…Recently, Patureau and co-workers reported an interesting dehydrogenative coupling of N-H carbazoles with secondary anilines under ruthenium catalysis to produce N-(2-aminophenyl)carbazoles. 15 In the present reaction, it would be possible for 3a to form via a similar dehydrogenative coupling of 1a with once formed 2a. However, this pathway could be excluded by crossover experiments with the addition of substituted carbazoles.…”

Cu‐Catalyzed Cross‐Dehydrogenative ortho‐Aminomethylation of Phenols

“…It should moreover be noted that no solvent performed better than cumene. [4,9] Conversely,b enzene and tert-butylbenzene are both tolerated as solvents,a lbeit with lower yields (Entries 6a nd 8), thus indicating that the benzylic C À H position is not essential. Theh igher performance of the cumene solvent may suggest the ability of persistent cumyl radicals to act as radical reservoirs in the reaction.…”