PHOTOCHEMISTRY OF 2H-AZIRINE - FORMATION OF NITRILE YLIDE EVIDENCED BY LASER FLASH-PHOTOLYSIS AND PULSE-RADIOLYSIS

Laser flash photolysis of 3-(4-biphenylyl)-2H-azirine (AZ) was carried out in cyclohexane for the direct detection of a nitrile ylide (NY). Two kinds of transient species, triplet AZ(T1) and NY, have been measured. Decay rates of these species were determined to be 6.7 x 10(5) s-1 (T1) and 8 x 10 s-1 (NY). The rate constants for the reactions of NY toward acetone and acrylonitrile were determined to be 2.5 x 10(3) dm3 mol-1 s-1 and 2.3 x 10(6) dm3 mol-1 s-1, respectively. These results were supported by the results of pulse radiolysis of AZ in benzene and stational irradiations of AZ.