Preparation of New Polyfunctional Magnesiated Heterocycles Using a Chlorine−, Bromine−, or Iodine−Magnesium Exchange
作者:Mohamed Abarbri、Jérôme Thibonnet、Laurent Bérillon、Florian Dehmel、Mario Rottländer、Paul Knochel
DOI:10.1021/jo000235t
日期:2000.7.1
iodine-magnesium exchange. In many cases, the exchange can be extended to heteroaryl bromides, and a case of a chlorine-magnesium exchange is described with tetrachlorothiophene. This new preparation of functionalized heteroarylmagnesium compounds provides after reaction with various electrophiles a new entry to a broad range of polyfunctional pyridines, imidazoles, furanes, thiophenes, pyrroles, antipyrines
杂芳基碘化物与i-PrMgBr(约1.0当量)在THF中的反应提供了相应的镁化杂环。如果可以在-20摄氏度以下进行交换,这些新的格氏试剂中可以容忍酯基,氰基或氯化物等官能团。对于所有带有吸电子基团或螯合官能团的杂环,这种情况都有利于碘镁交换。在许多情况下,交换可扩展至杂芳基溴,并且描述了用四氯噻吩进行氯镁交换的情况。在与各种亲电试剂反应后,这种新的官能化的杂芳基镁化合物的制备为广泛的多官能吡啶,咪唑,呋喃,噻吩,吡咯,安替比林和尿嘧啶衍生物提供了新的入口。