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Clamp compounds (Pincer complexes) has a wide range of applications in many fields , it has both the characteristics of the metal organic and coordination chemistry , both containing C-Mσ key , another Donor-Metal coordination role , it has become in recent years research of a hot spot . Currently in the field most of the studies have focused on the [N, C, N] -type compound , there are also some [ P , C , P -type and [S, C, S] -type compound . Therefore , on this basis , we design a symmetric clamp type ligands with an oxazoline group , and the group with electron-withdrawing effect of positioning the metalation reaction . M-xylene feedstock , after a series of reactions resulting novel [ N , N ] type ligand [ 4,6 - dibromo - 1,3 - bis ( 2'- oxazolin- yl)] benzene . This compound with palladium acetate reaction mixture containing [ N , C, N ] type of palladium compound , and the latter with the reaction with lithium chloride , to obtain the corresponding chloro palladium compound ; palladium compound and in this study based on the ring in the Suzuki reaction . application . Each step of the above structure of the product were confirmed through IR, 1H-NMR, 13C-NMR . Study this new [N , C, N] the clamp ring palladium compound catalyzed aryl halides with benzene boronic acid Suzuki coupling reaction was investigated solvent solvent , reaction temperature, reaction time, the reaction system pH of the Suzuki coupling linking reaction , the study found that the 1,4 - dioxane as solvent , K2CO3 as the base, under the conditions of 80 ° C , the reaction for 10 hours under optimal conditions , the Suzuki coupling reaction of aryl halides with phenylboronic acid best catalytic effect . Based on the above , and explore the Suzuki coupling reaction The palladium catalyzed replace chlorobenzene with phenylboronic acid ( methyl, methoxy , nitro ) . The results show that : the palladium compound having a wide range of substrate (including the electron donating groups and electron withdrawing group) , and high catalytic activity ( the amount of catalyst is only 0.1mol% , and the yield is higher ) , mild reaction conditions ( at 65 ℃ reaction 10 hours) .
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