Nanosecond laser flash photolysis study of photochemical ring opening in phenyl aziridines

ORGN 97

Paritosh K. Das, pdas@cameron.edu, Physical Sciences Department, Cameron University, 2800 W. Gore Boulevard, Lawton, OK 73505
Based on pulsed laser excitations and nanosecond kinetic spectrometry, a time-resolved study has been performed on ring opening in phenyl aziridines in solutions under various conditions of photoexcitation, namely, direct excitation (lex = 266 nm), triplet energy transfer from acetone (lex = 308 nm) and reversible electron transfer sensitization by 1,4-dicyanonaphthalene singlet ((lex = 337 nm). In all cases, the ring-opened azomethine ylides have been observed and characterized as transient species in solutions at room temperature. This paper will focus on the kinetic data concerning transient behavior and reactivity of azomethine ylides and will compare photochemical ring opening characteristics of phenyl aziridines with those of phenyl oxiranes.