Pinacol coupling reactions catalyzed by active zinc revealed high activity and extensive suitability. The efficiency of the reaction was improved apparently owing to decreasing reductive potential of zinc. In addition...Pinacol coupling reactions catalyzed by active zinc revealed high activity and extensive suitability. The efficiency of the reaction was improved apparently owing to decreasing reductive potential of zinc. In addition, the results indicated that the zinc activity has a direct relation to the coupling reactivity compared to untreated zinc or other general active zinc.展开更多
The reduction of TiCl4(THF)2 with Al in CH2Cl2 gave a green solution of [Ti2(μ-Cl)2Cl4· (THF)4] (1) which was found to promote the reductive homocoupling of aromatic aldehydes to yield symmetrical 1, 2-diols wit...The reduction of TiCl4(THF)2 with Al in CH2Cl2 gave a green solution of [Ti2(μ-Cl)2Cl4· (THF)4] (1) which was found to promote the reductive homocoupling of aromatic aldehydes to yield symmetrical 1, 2-diols with high diasterepselectivities.展开更多
A convenient pinacol coupling of aromatic aldehydes and aryl methyl ketones has been achieved with high yields by aluminum powder in the presence of oxalic acid in water. However, the diastereoselectivities of pinacol...A convenient pinacol coupling of aromatic aldehydes and aryl methyl ketones has been achieved with high yields by aluminum powder in the presence of oxalic acid in water. However, the diastereoselectivities of pinacols were not satisfying, and most aliphatic aldehydes and diaryl ketones have been found to be unreactive under the same conditions.展开更多
基金supported by the National Natural Science Foundation of China(No.20472079)
文摘Pinacol coupling reactions catalyzed by active zinc revealed high activity and extensive suitability. The efficiency of the reaction was improved apparently owing to decreasing reductive potential of zinc. In addition, the results indicated that the zinc activity has a direct relation to the coupling reactivity compared to untreated zinc or other general active zinc.
文摘The reduction of TiCl4(THF)2 with Al in CH2Cl2 gave a green solution of [Ti2(μ-Cl)2Cl4· (THF)4] (1) which was found to promote the reductive homocoupling of aromatic aldehydes to yield symmetrical 1, 2-diols with high diasterepselectivities.
文摘A convenient pinacol coupling of aromatic aldehydes and aryl methyl ketones has been achieved with high yields by aluminum powder in the presence of oxalic acid in water. However, the diastereoselectivities of pinacols were not satisfying, and most aliphatic aldehydes and diaryl ketones have been found to be unreactive under the same conditions.