Spectroscopic and Kinetic Characterization of Diphenyldiazomethane Radical Anion

Article abstract of DOI:10.1021/j100381a041

Diphenyldiazomethane radical anion (Ph2CN2^.-) has been generated by radiolytic reduction of diphenyldiazomethane (Ph2CN2) in both protic and aprotic solvents.The absolute kinetics of formation and reactivity of Ph2CN2^.- were obtained by monitoring its transient absorption (λ_max = 355-370 nm) following nanosecond pulse radiolysis.In isopropylalcohol, reaction of the solvated electron with Ph2CN2 forms Ph2CN2^.- (λ_max =355 nm), which subsequently protonates to form Ph2C^.N2H), as detected by a sharp absorption band at 330 nm.In aprotic solvents and in the ab sence of added quenchers, Ph2CN2^.- decays primarily by pseudo-first-order reaction with Ph2CN2.With added weak organic acids protonation of Ph2CN2^.- also occurs.Ph2CN2^.- reacts with molecular oxygen with a near diffusion-controlled rate; however, it demonstrates no reactivity toward hydrogen atom donors, and no evidence of thermal loss of N2 to produce diphenylcarbene radical anion was observed.