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Rates of 1-adamantyl fluoroformate with substituted pyridines (3-CH3,4-CH3 H,3-C1,3,4-(CH3)2,3,5-(CH3)2) in methanol have been measured by conductometric method at various temperatures and concentrations. The activation parameters (△H≠ , △S ≠ ) and Hammett reaction constant (p) or Br￠nsted coef-ficient (β) were evaluated from rate constant. The activation entropies are large and negative, and the activation enthalpies are small and positive The Hammett reaction constant (p) and Br￠nsted coefficient (β)values were -4.15 and 0.63, respectively. From the above results,it may be concluded that this reaction proceeds to a concerted displacement mechanism in methanol.
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