ORGANIC MIXED-VALENCE SYSTEMS .2. 2-CENTERS AND 3-CENTERS COMPOUNDS WITH META CONNECTIONS AROUND A CENTRAL PHENYLENE RING

This paper is devoted to two new aromatic polyamines derived from p-EF TP henyl)-N,N,N',N'-tetrakis(4-ethylphenyl)-1,1':3',1 ''-terphenyl-4,4 ''-diamine) and exhibiting meta connections around a central phenylen e ring. In p-EFDP henyl-(N,N,N',N'-tetrakis(4-ethylphenyl)-1,1':3',1 ' '-terphenyl-4,4 ''-diamine) there are only two redox sites instead of three. Upon partial oxidation, an intervalence transition is observed from which an electronic coupling very similar to the one of p-EFTP is obtained. In p-FADP (N,N,N',N',N '',N ''-hexakis(4-ethylphenyl)-1,1': 3',1 ''-terphenyl-4,4 '',5' triamine) one finds two redox sites of the N,N'-bis(4-ethylphenyl)-4-aminobiphenyl type, and one redox site of t he triphenylamine type. The analysis of the electrochemical behavior a nd of the intervalence transitions in the mono- and dioxidized species allows the distinction among the different types of electron transfer .