申请人:THE DOW CHEMICAL COMPANY
公开号:EP0243853A2
公开(公告)日:1987-11-04
2- and 4-(Dichloromethyl)pyridines containing electron withdrawing substituents on the ring are prepared by the reaction of the corresponding 2- or 4- halopyridines with excess chloroform in the presence of a strong base in a medium containing a dipolar aprotic solvent or a phase transfer catalyst. 3-Chloro-5-(trifluoromethyl)-2-(dichloromethyl)pyridine, for example, is prepared by the reaction of 2,3-dichloro-5-(trifluoromethyl) pyridine with chloroform in the presence of sodium hydroxide and N-methylpyrrolidone. Substituted 2-(dichloromethyl)pyridines are useful as agricultural pesticides and as intermediates for the preparation of agricultural pesticides.
在环上含有取电子取代基的 2-和 4-(二氯甲基)吡啶是通过相应的 2-或 4-卤代吡啶与过量氯仿在强碱存在下,在含有双极性非烷基溶剂或相转移催化剂的介质中反应制备的。例如,3-氯-5-(三氟甲基)-2-(二氯甲基)吡啶是由 2,3-二氯-5-(三氟甲基)吡啶与氯仿在氢氧化钠和 N-甲基吡咯烷酮存在下反应制备的。取代的 2-(二氯甲基)吡啶可用作农用杀虫剂和制备农用杀虫剂的中间体。