Ionenpaareffekte bei der Photolyse und Thermolyse von Aryldiazonium‐tetrafluoroboraten

Abstract

Ion Pair‐Effects in the Photolysis and Thermolysis of Arenediazonium Tetrafluoroborates Fluoroarenes produced by Schiemann‐reaction of p‐methyl‐ and p‐tert.‐butyl‐benzenediazonium tetrafluoroborates in solution are formed mainly from ArN 2 + /BF 4 − ‐ion pairs. The ratio of product yields formed from the reaction of arene cations with the solvent to the yields of fluoroarenes increases with increasing K D /α; K D is the conductometrically determined dissociation constant, and α the dissociation degree of ion pairs. The photochemical and thermal dediazoniation gives the same product ratios, indicating, that both sorts of reactions proceed via the same intermediate — the arene cation.