Beschreibung:
<jats:title>Abstract</jats:title>
<jats:p> The autoxidation of adrenalone and other 4-acyl-catecholamines in the presence of diorganothalliumhydroxide are investigated by ESR-spectroscopy. On the basis of the counterion splitting and the proton coupling constants as well as the g-values a semi-quinone structure was established. By comparing several monosubstituted o-benzosemi-quinones an increment system for the assignment of the different proton coupling constants was developed. The agreement between experimental and calculated values is good for all compounds investigated. Prolonged autoxidation of adrenalone yields a stable para-magnetic secondary product.</jats:p>