Notes. Co-ordination kinetics of some aliphatic amines towards the photogenerated transient ‘CoH{PPh(OEt)2}3’

Abstract

Time-resolved absorption spectra were observed after nitrogen-laser flash photolysis of toluene solutions of [CoHL₄][L = PPh(OEt)₂] in the presence of some aliphatic amines, and second-order rate constants were evaluated for co-ordination of the amines to the co-ordinatively unsaturated transient ‘CoHL₃’ photogenerated. The steric bulk of substituents on the amine nitrogens is a dominant factor in the magnitude of the constants. The CoHL₃(amine) adducts were also formed upon continuous photolysis with a high-pressure mercury lamp, and found to be stable at temperatures lower than –40 °C, on the basis of their ³¹P n.m.r. and visible absorption spectra.