ON THE APPARENT LACK OF OXYGEN QUENCHING OF TRIPLET EXCITED-STATES

The early observation that excited triplet states obtained chemically from trimethyldioxetane land subsequent energy transfers) appeared not to be quenched by oxygen is now shown to be an artifact; acetaldehyde is a product of the reaction and via chemical reactions it scavenges oxygen present in the medium; the attendant extended lifetime of the t riplet states then permits their employment in photochemical-type reac tions. The effect of the aldehyde can be over-ridden through an effici ent introduction of an excess of oxygen into the liquid reaction phase .