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The biphenyl structure ellagic acid derivatives have a strong biological activity, also can be used as chiral ligands used in asymmetric catalysis. Therefore, the synthesis of its derivatives is of great significance. This paper focuses on 4,4 ', 5,5', 6,6 '- hexamethoxymethyl -2,2' - biphenyl dicarboxylic acid dimethyl ester, 4,4 ', 5,5', 6,6 ' - Rokko group -2,2 '- biphenyldicarboxylic acid, 4,4', 5,5 ', 6,6' - hexaethoxylated -2,2 '- biphenyl dicarboxylic acid diethyl ester, 3 3'-dibenzyl -4,4 ', 5,5' - tetra-Benzyloxy ellagic acid, 3,3 '- dibenzyl -4,4', 5,5 ', 6,6' - Six benzyloxy-biphenyl dicarboxylic acid dibenzyl ester, 3,3 '- dibenzyl 4,4', 5,5 ', 6,6' - six-benzyloxy-biphenyl-dimethanol, camphorsulfonic acid -3 3'-dibenzyl -4,4 ', 5,5', 6,6 '- the six-benzyloxy-biphenyl-dimethanol ester, 3,3' - dibenzyl--4,4 ', 5,5' , 6,6 '- Six-benzyloxy linking terephthalic acid synthesis. 1) Synthesis of Biphenyldicarboxylate derivatives of ellagic acid as raw materials, protection of the phenolic hydroxyl groups of ellagic acid, methyl (ethyl) step to give 4,4 ', 5,5', 6,6 '- hexamethoxymethylmelamine -2,2 '- biphenyldicarboxylic acid dimethyl (4,4', 5,5 ', 6,6' - hexaethoxylated -2,2 '- biphenyl dicarboxylic acid diethyl ester) . Mild reaction conditions, this method has the steps, the process is relatively simple operation, to use reagents few advantages. 4,4 ', 5,5', 6,6 '- hexamethoxymethyl -2,2' - biphenyldicarboxylic acid dimethyl ester and potassium hydroxide in tetrahydrofuran, methanol, and distilled water (volume ratio 1:1:1 reflux) a mixed solution system successfully synthesized 4,4 ', 5,5', 6,6 '- hexamethoxymethyl -2,2' - biphenyldicarboxylic acid. IR, 1H-NMR spectrum analysis prove that the synthetic material of the target product. 2) the synthesis of chiral ligands biphenyls ellagic acid as raw materials, the phenolic hydroxyl group of the benzyl protecting Synthesis of 3,3 '- dibenzyl -4,4', 5,5 '- four benzyloxycarbonyl group ellagic acid; opening of the lactone ring to give 3,3 '- dibenzyl 4,4', 5,5 ', 6,6' - biphenyldicarboxylic acid dibenzyl ester six benzyloxy; dibenzyl ester reduction to give 3,3 '- dibenzyl-4, 4', 5,5 ', 6,6' - six-benzyloxy-biphenyl-dimethanol; glycols and camphor sulfonyl chloride to obtain camphorsulfonic acid, 3,3 '- dibenzyl -4,4 ', 5,5', 6,6 '- a six benzyl group biphenyl the dimethanol ester; dibenzyl ester hydrolysis to give 3,3' - dibenzyl -4,4 ', 5, 5 ', 6,6' - six benzyloxy-biphenyl dicarboxylic acid, cinchonine, 3,3 '- two benzyl -4,4', 5,5 ', 6,6' - six (benzyloxy) biphenyl dicarboxylic acid splitting to obtain R-3, 3'-dibenzyl -4,4 ', 5,5', 6,6 '- six benzyloxy-biphenyl dicarboxylic acid. Resolution of 3,3 '- dibenzyl and try -4,4', 5,5 ', 6,6' - six (benzyloxy) biphenyl-dimethanol. The analysis demonstrated that the synthetic material of the target product by IR, 1H-NMR, 13C-NMR and MS spectra. Meanwhile, the 3,3 '- dibenzyl -4,4', 5,5 '- tetra-benzyloxy-ellagic acid, and 3,3' - two benzyl -4,4 ', 5,5', 6,6 '- the six benzyl oxy associated phthalate benzyl ester synthesis reaction mechanism was discussed. The synthetic route of these products relative to other routes, such as Route (Ullamnn reaction) or route (Gettermann reaction), a few steps, simple operation, and the advantages of fewer reagents used. Is more important is a short reaction route, it relative to other routes, having a higher total yield.
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