2-(4-chlorop henyl)-4，5-dihydro-1-methyl-5-(trifluoromethyl)-1H-pyr role-3-carbonitrile

The preparation method is prepared by reacting 2-p-chlorophenyl-N-trichloroacetyl sarcosine with acrylonitrile. Add 5.1g (0.05mol) acetic anhydride, 1.6g (0.03mol) acrylonitrile and 10 drops of triethylamine to the acetonitrile solution of 6.2g (0.02mol) 2-p-chlorophenyl-N-trichloroacetylsarcosine In the medium, the reaction mixture was heated under reflux for 5.5 hours, cooled, and concentrated in vacuo to obtain a red oil. Add 9:1 (volume ratio) n-hexane and ethyl acetate mixed solvent to dissolve, filter with a sand core funnel filled with silica gel, and wash the filter residue with a mixed solvent of dichloromethane and ethyl acetate. After the filtrate is desolventized, the crude product 5.1 is obtained. g, the yield is 80%, and the product is recrystallized with dichloromethane.

This product is an intermediate of the insecticide chlorfenapyr.