TECHNOLOGY FOCUS - ELECTRONICS - Preferred Components: In the device, the layer containing (I) has a doped region and at least one region, which is less than the doped region, as doped or undoped region. The layer is a hole transport layer or emitter layer.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preparation (Disclosed): Preparation of (I) comprises coupling of 44,4''-dibromo-p-terphenyl with an aryl amine compound of formula (Ar1-NH2-Ar2) in the presence of bis(dibenzylideneacetone)palladium, tri-tert-butylphosphine and potassium-tert-butoxide to obtain aryl amine-terphenyl compound of formula (Ib) (representation of (I)) N.B. Ar1 and Ar2 are not defined. Preferred Definitions:    R1 = beta -naphthyl or 1,1'-biphenyl-4-yl;    R3 = H or CH3; and    R2 = CH3, isopropyl or tert.butyl.    SPECIFIC COMPOUNDS - 20 Compounds (I) are specifically claimed e.g. N4,N4''-di(naphthalen-1-yl)-N4,N4''-di-p-tolyl-(1,1':4',1''-terphenyl)-4,4''-diamine of formula (Ia), N4,N4''-di(naphthalen-2-yl)-N4,N4''-di-p-tolyl-(1,1':4',1''-terphenyl)-4,4''-diamine, N4,N4''-di((1,1'-biphenyl)-4-yl)-N4,N4''-di-p-tolyl-(1,1':4',1''-terphenyl)-4,4''-diamine, N4,N4''-bis(4-isopropylphenyl)-N4,N4''-di(naphthalen-2-yl)-(1,1':4',1''-terphenyl)-4,4''-diamine and N4,N4''-Bis(4-(tert-butyl)phenyl)-N4,N4''-di(naphthalen-2-yl)-(1,1':4,1''-terphenyl)-4,4''-diamine.    EXAMPLE - p-Toluidine (10.1 g), palladium(II)acetate (490 mg), 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (2.03 g), cesium carbonate (35.4 g) and 1-naphthylbromide (15 g) were dissolved in dioxane (210 ml), refluxed at 125 degrees C for 24 hours and purified to obtain N-(p-tolyl)-naphthalen-1-amine (12.7 g, purity 99.7%). N-(p-Tolyl)-naphthalen-1-amine (3.97 g) tri-tert-butylphosphine (47 mg), 4,4''-dibromo-p-terphenyl (3 g), bis(dibenzylideneacetone)palladium (89 mg) and potassium tert-butoxide (2.60 g) in toluene (75 ml) were stirred for 18 hours at 80 degrees C. The obtained mixture was filtered and concentrated and the obtained precipitate was added into dichloromethane/n-hexane to give N4,N4''-di(naphthalen-1-yl)-N4,N4''-di-p-tolyl-(1,1':4',1''-terphenyl)-4,4''-diamine (5.24 g, purity 97.8%).