作者:G. Zvilichovsky
DOI:10.1016/0040-4020(75)87042-6
日期:1975.1
4-(p-Nitrophenyl)-3,5-dihydroxyisoxazole is a remarkably strong acid which possesses unique chemical reactivity towards carbonyl compounds. It has been shown that these properties are encountered in a series of related 3,5-dihydroxyisoxazole derivatives. It appears that this isoxazole system is very electron deficient, a fact that together with a neighboring group effect is responsible for the exceptional
4-(对硝基苯基)-3,5-二羟基异恶唑是一种非常强的酸,对羰基化合物具有独特的化学反应性。已经表明,在一系列相关的3,5-二羟基异恶唑衍生物中遇到了这些性质。看来该异恶唑体系非常缺乏电子,这一事实是与邻近基团效应共同导致了优异的酸度和反应性。电子的缺乏还反映在芳族质子的去屏蔽作用上。NMR光谱的比较用作异恶唑部分的电子缺乏的标准。这类新的酸产生了各种新颖的系统。讨论了取代对苯甲醛衍生物制得的醛二铵体系可见光谱的影响。