Flash photolysis observation and lifetimes of 2-fluorenyl-and 4-biphenylylacetylnitrenium ions in aqueous solution

Laser flash photolysis is employed for the observation of 2-fluorenyl- and 4-biphenylylacetylnitrenium ions in aqueous solution. Kinetic stabilities of arylnitrenium ions have been demonstrated by direct measurements and are compared with those of carbenium ions. Reaction of nitrenium ions with carbon nucleophiles occurs at the external nitrogen. The 'Azide-clock' method is employed to study the lifetimes of nitrenium ions.