Use of tertiary amino-groups as substituents to stabilise compounds towards attack by singlet oxygen

Abstract

An alkene, a dihydropyran, a furan, and an anthracene, each having a tertiary amino-substituent insulated from the olefinic system, have been shown to be particularly stable towards singlet oxygen generated by irradiation of methanolic solutions of Methylene Blue. The stability is attributed to the amino-group quenching the singlet oxygen. Addition of triethylamine or 1,4-diazabicyclo[2,2,2]octane to solutions of 2-methylfuran and anthracene also reduces the rate of oxidation of the latter compounds but much less efficiently.