Characterization of two hydroxytrichloropicolinic acids: application of the one-bond chlorine-isotope effect in13C NMR
作者:Nicholas M. Irvine、David H. Cooper、Scott Thornburgh
DOI:10.1002/mrc.2196
日期:2008.5
The structures of 4‐hydroxy‐3,5,6‐trichloropyridine‐2‐carboxylic acid (1a) and 6‐hydroxy‐3,4,5‐trichloro‐2‐carboxylic acid (1b) were verified by the NMR analysis of their corresponding methylated and decarboxylated derivatives 2,3,5‐trichloro‐4‐methoxypyridine (5) and 3,4,5‐trichloro‐2‐methoxypyridine (8), respectively. The 6‐hydroxy isomer (1a) was found to be in equilibrium with its pyridinone tautomer
4-羟基-3,5,6-三氯吡啶-2-羧酸(1a)和6-羟基-3,4,5-三氯-2-羧酸(1b)的结构通过核磁共振分析证实。相应的甲基化和脱羧衍生物 2,3,5-三氯-4-甲氧基吡啶 (5) 和 3,4,5-三氯-2-甲氧基吡啶 (8),分别。发现 6-羟基异构体 (1a) 与其吡啶酮互变异构体处于平衡状态,这可以通过形成大量 3,4,5-三氯-1-甲基-6-氧代-1,6-二氢吡啶-2 来证明-羧酸甲酯(6b)完全甲基化。单键氯同位素效应已被使用并证明是在 13C NMR 光谱中识别氯化碳的有效工具,为解决氯化化合物的结构问题提供了额外的工具。版权所有 © 2008 John Wiley & Sons, Ltd.