双吡啶盐及其聚合物的研究Ⅱ.4,4’-(-1,4-苯撑-)-双-[N-烷(芳)基-2,6-二苯基]-吡啶盐及其聚合物对某些芳香酮还原反应的催化作用

Studty on Bipyridinium Salts and Their Polymers Ⅱ Catalysis of 4, 4- (1,4-phenylene-)bis-(N-alykyl(aryl)-2, 6-diphenyl)-pyridinium Salts and Their Polymers For the Reduction of Some Aromatic Ketones

在4,4’-(1,4-苯撑)-双-IN-烷(芳)基-2,6-二苯基I吡啶盐及其聚合物的催化下,二苯甲酮和苯乙烯基苯甲酮与中性条件下的锌粉发生双分子还原反应,生成相应的邻二叔醇;而结构类似的环状酮却主要发生单分子还原反应.双吡啶盐及其聚合物的结构和反应介质的极性对还原反应的速度有很大影响。本文对催化反应的机理也进行了讨论。

Under the catalysis of 4,4-(1,4--phenylene)--bis--(N---pyridinium salts and their polymers, benzophenone and chalkone were reduced with abimolecular mechanism by zinc powder to produce corresponding pinacols. But theproducts of monomolecular reduction were obtained for two analogous cycloketones.The catalytic effect of various bipyridinium salts and their polymers and the influenceof the solvents for the reduction of benzophenone was compared. The mechanism ofthe catalytic reduction was also discussed.