Fluoronated heterocyclic compounds: Selective chlorine/fluorine exchange reactions on pyridazines
作者:E. Klauke、L. Oehlmann、B. Baasner
DOI:10.1016/s0022-1139(00)81214-2
日期:1983.10
of the three possible difluorinated pyridazines and the two possible trifluorinated pyridazines. The hydrogen fluoride reaction is an equilibrium reaction in which the substitution of the first chlorine for fluorine also occurs exclusively in the 3-position. Double chlorine/fluorine substitution only gives 3,6-difluoro-4,5-dichloropyridazine, triple substitution only producing 3,4,6-trifluoro-5-chloropyridazine
这项工作描述了在四氯哒嗪上的选择性氯/氟取代反应。氟化钠,氟化钾和氟化氢被用作氟化剂。已经发现,在第一氟化阶段中的氟化钠和氟化钾产生被在3位上结合的氯的氟唯一取代。二氟化和三氟化产生三种可能的二氟化哒嗪和两种可能的三氟化哒嗪的混合物。氟化氢反应是一种平衡反应,其中第一氯取代氟也仅在3位发生。双重氯/氟取代仅产生3,6-二氟-4,5-二氯哒嗪,三次取代仅产生3,4,6-三氟-5-氯哒嗪。