REACTION-KINETICS OF O(P-3) WITH ACRYLONITRILE AND CROTONONITRILE

The reaction of oxygen atoms O(P-3) with unsaturated nitriles (RCN), v iz. acrylonitrile (CH2=CHCN), and crotononitrile (CH3CH=CHCN), was stu died in a flow discharge tube in the pressure range 1.2-1.7 Torr using the O(P-3) chemiluminescence titration method. The rate constants for the reaction O(P-3)+RCN-->products was determined at room temperature to be (4.9+/-1.0)x10(-13) and (5.4+/-0.8)x10(-13) cm(3) molecule(-1) s(-1) for acrylonitrile and crotononitrile respectively. The activatio n energies for the above reactions were estimated using the MNDO metho d. The formation of a biradical involving the addition of an oxygen at om to the double bond is proposed as the major channel for the reactio n. (C) 1997 Elsevier Science B.V.