3′,4′,5′-三氟联苯-4-硼酸的合成及表征  

Synthesis and characterization of 3',4',5'-trifluorobiphenyl-4-boronic acid

作　　者：李月琴[1] 陶弦[1] 徐慧华[1] 沈应中[1] 

机构地区：[1]南京航空航天大学材料科学与技术学院应用化学系,江苏南京210016

出　　处：《化学试剂》2010年第5期455-457,共3页Chemical Reagents

基　　金：江苏省自然科学基金资助项目(BK2007199)

摘　　要：使用工业上易得的原料通过3步反应合成标题化合物。苯硼酸与3,4,5-三氟溴苯作为起始原料,在K2CO3水溶液和甲苯体系中,Pd/C催化反应生成3,4,5-三氟联苯,产率80%。接着3,4,5-三氟联苯在CCl4中经过Fe+I2催化溴化得到4′-溴-3,4,5-三氟联苯,产率75%。4′-溴-3,4,5-三氟联苯与n-BuLi在-78℃下反应生成3′,4′,5′-三氟联苯-4-锂,然后与硼酸三正丁酯-78℃反应,最后在室温下酸性条件下水解生成目标产物,产率86%。合成路线的总收率达到51.6%。合成的化合物用元素分析、FT-IR、1HNMR和13CNMR等手段进行了表征。3＇,4＇,5＇-Trifluorobiphenyl-4-boronic acid was synthesized via a three-step reaction process with commercially available materials.Phenylboronic acid and 3,4,5-trifluorobromobenzene were used as starting materials under the catalytic action of Pd/C in a system composed of K2CO3 solution and toluene to give a biaryl intermediate 3,4,5-trifluorobiphenyl in 80% yield.Then 3,4,5-trifluorobiphenyl was exclusively brominated by Br2 in CCl4 in the presence of Fe＋I2 catalysts to give 4＇-bromo-3,4,5-trifluorobiphenyl in 75% yield.4＇-Bromo-3,4,5-trifluorobiphenyl then reacted with n-BuLi to give（3＇,4＇,5＇-trifluorobiphenyl-4-）lithium at-78 ℃,which was then boronylated by B（O-nBu）3 at the same temperature and hydrolyzed by acid at room temperature to give the desired compound in 86%.The total product yield was up to 51.6%.The synthesized product was characterized by elemental analysis,FT-IR,1HNMR and 13CNMR,respectively.

关 键 词：3 4 5-三氟联苯 三氟取代 芳基硼酸 

分 类 号：TQ314.248[化学工程—高聚物工业]