A new method for the synthesis of multiarylanthracenes was developed by means of the RuH(2)(CO)(PPh(3))(3)-catalyzed arylation of anthraquinone with arylboronates. This method consists of short and straightforward sequences starting with an easily accessible anthraquinone and is applicable to the syntheses of various multiarylanthracenes including those bearing twisted backbones.

Ruthenium-catalyzed C-H arylation of aromatic nitriles with arylboronates is described. The use of RuH(CO){P(4-MeCH)} as a catalyst provided higher yields of the ortho arylation products than the conventional RuH(CO)(PPh) catalyst. The arylation takes place mostly at the ortho positions, but unprecedented para arylation was also partially observed to give ortho,para diarylation products. In addition to C-H bond cleavage, the cyano group was also found to function as a directing group for cleavage of C-O bonds in aryl ethers.

A new convenient method for the synthesis of dibenzo[a,h]anthracenes and picenes using ruthenium-catalyzed regioselective C–H arylation of aromatic ketones has been developed. Acetophenone derivatives and 1,4-benzenediboronates were coupled in 2:1 ratios to form p-terphenyl derivatives. Conversion of the acetyl group to an ethynyl group, followed by cycloaromatization provided the desired fused aromatic compounds. An organic field-effect transistor fabricated from one of these products gave moderate hole mobility.

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A convenient method for the synthesis of tetraalkylanthracenes and -pentacenes by means of ruthenium-catalyzed regioselective C-H alkylation of the corresponding acenequinones was developed. Dialkyldiarylpentacene was also synthesized using chemoselective tandem C-H alkylation/C-O arylation of dimethoxypentacenequinone. It was suggested that a tetraalkylpentacene is stable under air in the dark and possesses an appropriate HOMO level as active material for p-type organic field-effect transistors (OFETs).