selective gas phase chlorination of polychlorinated picolines beta for the preparation of 2,3,5,6-tetrachloropyridine and their precursors.

摘要

2,3,5,6-TETRACLOOPIRIDINA, 2,3,6-trichloro AND-5 (trichloromethyl) pyridine is prepared by chlorinating SELECTIVE BETA-picolines polychlorinated IN THE VAPOR PHASE 250 (degrees) CY 450 ( GRADES) C catalyst IN ACID ALURO "LEWIS" SPECIFIC PRESENCE on an inorganic support. THE GAMMA POSITION NO pyridine ring is usually chlorinated starting material or products REACTION. THESE PRODUCTS compounds are useful as intermediates for producing insecticides and herbicides.