钯催化下2,5-二溴噻吩与对甲氧基苯硼酸的偶合反应研究
Study on coupling reaction between 2,5-dibromothiophene and 4-methoxylphenylboronic acid under catalysis of palladium (0)
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摘要: 采用H2O2-HBr连用的方法对2,5-二溴噻吩的合成进行了改进,并研究了Pd(PPh3)4催化下2,5-二溴噻吩与对甲氧基苯硼酸在不同碱溶液中发生的偶合反应,采用饱和NaHCO3溶液可获得单边偶合产物Ⅰ;而采用Na2CO3溶液可获得双边偶合产物Ⅱ;采用CsCO3作为碱时,没有偶合反应发生.Abstract: 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.