On the alcohol- and water-catalyzed tautomerization of vitamins K1- and K2-derived quinone methide intermediates.
On the alcohol- and water-catalyzed tautomerization of vitamins K1- and K2-derived quinone methide intermediates.
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维生素 K1 和 K2 衍生的醌甲基化物中间体的醇和水催化互变异构化。
DOI：
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发表时间：
2004
影响因子：
3.6
通讯作者：
D. Kuntz
中科院分区：
文献类型：
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作者：
A. Swartz;M. Barra;D. Kuntz
在羟基溶剂（ROH; R = H，烷基）存在下，测定了维生素K（1）和K（2）在CH（3）CN溶液中经激光闪光激发后，1，3-醌甲基化物转化为相应的1，2-醌甲基化物互变异构体的转化率。在所有的情况下，互变异构化过程中的ROH的存在下，加速，相应的观察到的速率常数显示出对ROH浓度的立方依赖。这种高阶依赖性归因于在每种情况下涉及3当量ROH的质子中继转移。
Rates of conversion of 1,3-quinone methides into the corresponding 1,2-quinone methide tautomers, formed upon laser-flash excitation of vitamins K(1) and K(2) in CH(3)CN solutions, were determined in the presence of hydroxylic solvents (ROH; R = H, alkyl). In all cases, the tautomerization process is accelerated in the presence of ROH, and the corresponding observed rate constants show a cubed dependence on ROH concentration. This high-order dependency is attributed to a proton-relay transfer involving 3 equiv of ROH in each case.