CHLORINE-ISOTOPIC EXCHANGE BETWEEN LITHIUM CHLORIDE AND SUBSTITUTED 2-CHLOROPYRIDINE IN HOMOGENEOUS SOLUTION

Article abstract of DOI:10.1016/S0040-4020(01)97730-0

The kinetics of chlorine-isotopic exchange between lithium chloride-36 and cyano- and nitro-substituted 2-chloropyridines were measured in sulpholane, acetone or methanol solution.Activating effects of ortho-nitro and ortho-azu substitution are compared: a nitro-group is 50 x as activating as the aza-group in the p-nitrochlorobenzene system, whereas it is the aza-function which is 3 times as activiting as the nitro group in the o-nitrochlorobenzene system.The effect of Me substituents placed ortho to an activating nitro-group was studied by comparing 2-chloro-3-cyano-5-nitropyridine and its 6-methyl- and 4,6-dimethyl derivatives.