申请人:E. I. Du Pont de Nemours and Company
公开号:US05138107A1
公开(公告)日:1992-08-11
A process is disclosed for chlorinating, brominating and/or iodinating an organic substrate containing both a single acidic hydrogen atom and at least one electron withdrawing group attached to the same carbon atom. The process replaces the single acidic hydrogen with chlorine, bromine and/or iodine and involves reacting the substrate in solution with a halogenating agent (e.g., a perhalomethane wherein the halogen substituents are I, Br and/or Cl, a trihaloacetic acid ester wherein the halogen substituents are Br and/or Cl, or a perfluoroalkyl halide wherein the halide is I, Br and/or Cl) in the presence of (i) a phase transfer catalyst of the formula R.sup.1 R.sup.2 R.sup.3 R.sup.4 LJ where L is selected from the group consisting of phosphorus and nitrogen, where J is an inorganic anion other than fluoride, and where R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are independently chosen from the froup consisting of hydrocarbyl radicals containing from 1 to about 20 carbon atoms and (ii) a mild inorganic base which is insoluble in the reaction medium.
揭示了一种用于氯化、溴化和/或碘化含有单个酸性氢原子和至少一个与同一碳原子连接的电子吸引基团的有机底物的过程。该过程用氯、溴和/或碘取代单个酸性氢,并涉及在溶液中将底物与卤化剂(例如,卤代代甲烷,其中卤素取代基是I、Br和/或Cl,三卤乙酸酯,其中卤素取代基是Br和/或Cl,或全氟烷基卤化物,其中卤素是I、Br和/或Cl)在(i)存在下反应,其中相转移催化剂的化学式为R.sup.1 R.sup.2 R.sup.3 R.sup.4 LJ,其中L选自磷和氮的群,J是除氟化物以外的无机阴离子,R.sup.1、R.sup.2、R.sup.3和R.sup.4独立地选择自含有1到约20个碳原子的烃基基团的群,和(ii)存在下的不溶于反应介质的温和无机碱。