The Cadmium-photosensitized Reaction of Saturated Tertiary Amines

Article abstract of DOI:10.1246/bcsj.54.3677

Rate constants for the quenching of the cadmium resonance line at 326.1 nm by triethylamine (TEA), N-ethylpiperidine (NEP), and 1-azabicyclo<2.2.2>octane (ABCO) were obtained.Relative rate constants for the formation of an exciplex between an excited cadmium atom and these amines and quantum yields for the emission from the exciplex were also obtained.Contrary to the case of primary amines, in which the electron-donating ability of the nitrogen atom is operative, the exciplex formation in the present case is mainly governed by the magnitude of the steric effect of ethyl groups on the ineraction between the nitrogen atom and an excited cadmium atom.Gaseous products were hydrogen, methane, ethane (and/or ethylene), and butane.The quantum yields of these products indicate that the primary photochemical products are methyl and ethyl radicals for TEA and NEP.The amount of products for ABCO was considerably smaller than those for other amines.