220995-49-3Relevant academic research and scientific papers
Metal-Free Oxidative C-C Coupling of Arylamines Using a Quinone-Based Organic Oxidant
Maddala, Sudhakar,Mallick, Sudesh,Venkatakrishnan, Parthasarathy
, p. 8958 - 8972 (2017/09/11)
A variety of arylamines are shown to undergo oxidative C-C bond formation using quinone-based chloranil/H+ reagent as the recyclable organic (metal-free) oxidant system to afford benzidines/naphthidines. Arylamines (3°/2°) designed with various substituents were employed to understand the steric as well as electronic preferences of oxidative dimerization, and a mechanism involving amine radical cation has been proposed. The tetraphenylbenzidine derivative obtained via oxidative C-C coupling has been further converted to blue-emissive hole-transporting material via a simple chemical transformation. This study highlights the preparation of novel HTMs in a simple, economic, and efficient manner.
Cu(II)-mediated generation of triarylamine radical cations and their dimerization. An easy route to tetraarylbenzidines
Sreenath, Kesavapillai,Suneesh, Chettiyam Veettil,Ratheesh Kumar, Venugopal K.,Gopidas, Karical R.
, p. 3245 - 3251 (2008/09/20)
(Chemical Equation Presented) Triphenylamine (TPA) derivatives react with Cu2+ in acetonitrile to give TPA radical cations which undergo dimerization and deprotonation reactions to yield tetraphenylbenzidines (TPB). Synthetic utility of this reaction is demonstrated using several triphenylamine derivatives, and yields in excess of 80% are obtained in most cases. Involvement of the amine radical cations in these reactions was confirmed by ESR and absorption spectroscopic studies. A mechanism consistent with all observations is proposed. This study also revealed a very good correlation between the free energy change for radical cation formation and product yields.
