The Unusual Reactivity of 9,9'-Dianthrylcarbene

Article abstract of DOI:10.1021/jo00261a012

9,9'-Dianthrylcarbene was investigated by using laser flash photolysis, conventional flash photolysis, and optical modulation spectroscopy.Its optical absorption spectrum was characterized by two strong bands at 355 nm (ε 3.9E4 M^-1cm^-1) and at 445 nm (ε 2.9E4 M^-1cm^-1).Although the carbene has a triplet ground state, the rate constant for spin-allowed reaction with oxygen was ca. 5E5 M^-1s^-1, yet it underwent self-reaction at the diffusion-controlled limit.These unusual kinetic properties stem from the fact the carbene has a structure in which the unpaired electrons are highly delocalized.