Study on coupling reaction between 2,5-dibromothiophene and 4-methoxylphenylboronic acid under catalysis of palladium (0)

An impoved method for synthesis of 2,5-bibromthiophene is reported.By using different bases in diferrent solvent,the coupling reaction between 2,5-dibromthiophene and 4-methoxylphenylboronic acid under the catalysis of palladium (0) provided different coupling products.The monosidecoupling product was obtained in 60% yield when NaHCO3 was used as base,doubleside coupling product was obtained when Na2CO3 was used,while no coupling product was obtained when CsCO3 was used.