NEW MATERIAL:The compound of formulaI.
USE: A starting material for poly(2,5-diethynylthiophene) useful as materials for organic semiconductors or conjugated organic electrically conductive materials having improved heat resistance.
PROCESS: A 2,5-dihalothiophene of formula II is reacted with a compound of formula III (R, R' and R" are alkyl, aryl or alkenyl) in the presence of an amine and a palladium compound, e.g. (R33P)2PdBr2 (R3 is alkyl, etc.) and a copper compound, e.g. CuCl or CuI, as a catalyst at 20W100°C and preferably in an inert gaseous atmosphere, e.g. N2. The resultant reaction product is then desilylated with a metallic halide, e.g. KF, KBr or NaF, to gie the compound of formulaI. The compound of formula III is preferably used in a molar amount of 2W2.5mol based on one mole compound of formula II. The amount of the amine is preferably 5l or more based on one mole compound of formula II.
ISAMOTO YOSHITSUGU
MATSUMURA YOSHIO
