Pd(dppf)Cl_2催化Suzuki偶联反应合成4-(4-叔丁基苯基)-6-甲基-1,2,3,5-四氢-s-引达省

Synthesis of 4-( 4-tert-Butylphenyl)-6-methyl-1,2,3,5-tetrahydros-indacene by Pd( dppf) Cl_2 Catalyzed Suzuki-Miyaura Cross Coupling Reaction

以Pd(dppf)Cl2为催化剂催化Suzuki偶联反应合成了一种在烯烃聚合中有重要作用的茂金属催化剂配体——4-(4-叔丁基苯基)-6-甲基-1,2,3,5-四氢-s-引达省(Ⅲ),其结构经1HNMR,IR,GC-MS和MS进行了表征。考察了催化剂、添加剂、溶剂的种类及其与反应物的配比等因素对反应的影响,得到的最佳合成工艺条件为:以底物4-溴-6-甲基-1,2,3,5-四氢-s-引达省计,摩尔分数1.5%Pd(dppf)Cl2,4-叔丁基苯硼酸1.1 mol/mol,无水碳酸钾1.5 mol/mol,异丙醇1 000 mL/mol,回流至溴代茚底物转化保持恒定(约需26 h),Ⅲ的收率为82.1%,GC纯度99%。探索出一种以溴代茚类化合物为底物合成联芳基茚类化合物的方法,有效控制了合成过程中"双键移位"副产物的产生。

4- [ （ 4-tert-Butyl ） phenyl ] -6-methyl-1,2, 3,5-tetrahydro-s-indacene （ m ）, an important ligand to prepare metallocene catalysts for olefin polymerization, was synthesized by Suzuki-Miyaura cross-coupling reaction catalyzed by Pd （dppf） Cl2. The structure of the product was confirmed by 1HNMR,IR, GC-MS and MS. The effects of the kinds of catalysts, solvents, and bases on the reaction were studied in detail. Calculated on the basis of 4-bromo-6-methyl-1,2,3,5-tetrahydro-s-indacene, the optimized conditions were determined as follows ： In the presence of 1.5 mol% of Pd （dppf） Cl2,1.1 moL/mol of 4-tert-butylphenyl boronic acid, 1.5 mol/mol of K2CO3 and 1000 mL/mol of i-PrOH, the reaction mixture was stirred under reflux until reaching stable conversion of the bromoindene （ ca. 26 h needed）. Under such conditions,the yield of Ⅲ was 82. 1% , and the purity was 99%. By this practical method,bromide indene was used as an intermediate to successfully prepare aryl substituted indene, and the forming of indene double bond isomers was effectively inhibited in the present system.