芳基氯参与Suzuki偶联反应

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Mitchell等报导了用dppb作钯的配体,能够有效地催化氯代芳杂类同芳基硼酸进行Suzuki反应,产率高达98%; 之后Wang Shen等用三环已基磷(PCy3)作钯的配体,发现此配体催化剂能够最有效地激活芳氯键,这可能是由于三环已基磷比三苯基磷有更多的电子,因而可以增加钯氧化插入芳氯键的能力,同时还发现在Pd(PCy3)Cl2催化下,邻对位吸电子取代芳基氯能更有效的进行反应。


反应实例

The following is a typical experimental procedure. Amixture of methyl trarts-3shlorociunamate (entry 18, Table 2) (393.2 mg, 2mmol), dichlorobis(tricyclobezylphosphine) palladium(73.8 mg, 0.10 mol),phenylboronic acid (292.6 mg. 2.4 mmol), and cesium fluoride (607 mg, 4.0 mmol)in  1-methyl-2-pyrrolidinone (NMP, 5 mL)was degassed by purging with nitrogen. The mixture was then heated at 100 ℃for 10 hours. The mixture was then partitioned between ethyl acetate (90 mL)and water (20 mL). The organic layer was separated, washed with water, dried,and concentrated} The residue was then purified by column chromatographyeluting with 50/50/5 toluene/hexane/ether to give the coupled product (466mg.98%).

TetrahedronLetter: Vol. 38, No. 32,pp. 5575-5578, 1997



1.0 equiv of aryl chloride, 1.5 equiv of boronic acid,3.0 equiv of KF, cat. Pd(OAc)2 , cat. (two ligands per Pd center), THF (1 mL per mmol of aryl chloride), room temperature.Reaction times  have not been minimized.

【Wolfe,J. P.; Buchwald, S. L. Angew. Chem., Int. Ed. Engl. 1999, 38,2413–2416.】


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