Electronic Effect of Substituejits on Phenoxyacetic Acids 441 



cule, one would have to postulate either displacement of a chlorine 

 or reaction at a meta position. The ring nitrogen atom would acti- 

 vate the substance for attack by an electron-rich reagent at the meta 

 position. Although it has not been shown in other systems that this 

 is sterically favorable, this seems more reasonable than the disj)lace- 

 ment of chlorine. Although it has been postulated that in the 6-fiuoro 

 compound fluorine might be displaced, evidence is still lacking to 

 support this point. 



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