Dual Nickel/Photoredox-Catalyzed Synthesis of N-formyl N,N'-Diaryl Ethylenediamines via Multiple C-N/C-C Coupling of Nitroarenes with Trimethylamine

N,N'-Diaryl ethylenediamines are common feedstocks in organic synthesis and important structural motifs in medicinal chemistry. Whereas the C-N formation reactions based on anilines and aryl halides are the most direct methods to access N,N'-diaryl ethylenediamines, the photocatalytic synthetic version remains undeveloped. Herein we describe the dual nickel/photoredox-catalyzed amination reaction using nitroarenes and trimethylamine as reaction substrates. This cascade transformation hinges on the multiple C-N and C-C coupling events based on the nitrogen radical and a-aminomethyl radical derived from nitroarene and trimethylamine, respectively. A variety of N-formyl N,N'-diaryl ethylenediamines can be obtained under the reaction protocol. Subsequent hydrolysis offers the N,N'-diaryl ethylenediamines for further derivatizations.

Automated summary

We describe a cascade transformation of nitroarenes and trimethylamine using dual nickel/photoredox catalysis, leading to the synthesis of N-formyl N,N'-diaryl ethylenediamines. The reaction involves multiple C-N and C-C coupling events based on nitrogen and α-aminomethyl radicals derived from the starting materials. The obtained products can further undergo hydrolysis for further derivatizations.