The dediazoniation reaction of arenediazonium ions is regarded as the one instance where a phenyl cation is a reaction intermediate.'$ One may reasonably ask whether there exists in the chemistry of the phenylium ion any behavior analogous to the widespread propensity to neighboring group effects among alkyl catior~ s.~,~ Participation by neighboring hydroxyl to form an epoxide is known in aliphatic chemistry both in the case of dediazoniation6 and in ...
