论文部分内容阅读
本文报告数种4,5-二羟基嘧啶(以静止铂微电极为阳极,以饱和甘汞电极为阴极)的极谱行为。 1.选定醋酸作溶剂。 2.2-甲基-4,5,6-三羟基嘧啶(Ⅹ),2-取代-5,6(4)-二羟基嘧啶(Ⅺ,Ⅻ,ⅩⅢ)以及5,6(4)-二羟基嘧啶(ⅩⅣ)都能氧化,波高随着浓度的增大而上升。在同一浓度下酸性愈强,氧化电位愈大。浓度和波高,pH和半波电位各具有定量关系。 3.2-甲基-4,5,6-三羟基嘧啶(Ⅹ)在硷性溶液中不形成波。 4.各种5-羟基嘧啶具有不同的E_(1/2)值。 5.5-位上无羟基的2,4-二羟基嘧啶,和5-位羟基受苯甲基保护的2-甲基4(6)-羟基-5-苯甲氧基嘧啶不起极谱氧化作用。 6.从理论上探讨了4,5-二羟基嘧啶的氧化过程。
This paper reports the polarographic behavior of several 4,5-dihydroxypyrimidines (stationary platinum microelectrodes as anodes and saturated calomel electrodes as cathodes). 1. Selected acetic acid as solvent. (X), 2-substituted-5,6 (4) -dihydroxypyrimidines (XI, XII and XIII) and 5,6 (4) -dihydroxypyrimidine (XIV) can be oxidized, wave height increases with increasing concentration. Acidity in the same concentration stronger, the greater the oxidation potential. Concentration and wave height, pH and half-wave potentials each have a quantitative relationship. 3.2-Methyl-4,5,6-trihydroxypyrimidine (X) No formation of waves in alkaline solution. 4. Various 5-hydroxypyrimidines have different E_ (1/2) values. Hydroxy-free 2,4-dihydroxypyrimidine at the 5.5-position, and 2-methyl 4 (6) -hydroxy-5-benzyloxypyrimidine whose hydroxy group is protected at the 5- . The oxidation of 4,5-dihydroxypyrimidine was theoretically discussed.