Modular Synthesis of Triarylamines and Poly(triarylamine)s through a Radical Mechanism

Abstract

A modular protocol for the triarylamine synthesis has been developed using diarylamines and electron-rich arenes, such as phenols, as the building blocks. The KI/KIO 4 system proves to be highly efficient for the cross-dehydrogenative coupling of phenothiazines/phenoxazines with phenols/anilines. A wide range of functional groups attached to both coupling partners were well tolerated. Through the manipulation of reaction temperatures, the sequential assembly of bis-triarylamines could be achieved to provide the unsymmetrically bis-aminated phenols efficiently. Furthermore, the multiple aminated polyphenols were rapidly constructed in good to high yields by a single operation.

Aromatic Amine Catalysts for the O2-Mediated Cross-Dehydrogenative Phenothiazination Reaction?

“…This reaction, which we originally discovered in 2015, 25 is highly specific to phenothiazines and phenols, such that it is being increasingly utilized as a benchmark oxidative coupling reaction for the development of diverse new technologies. 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 We have likewise utilized it in order to quantify the performance of all redox catalysts investigated in the present article. The aim was to investigate how far one can go in terms of redox catalytic activity in the absence of any heavy-atom-containing additives such as tellurium.…”