The formation and fragmentation of flavonoid radical anions

Abstract

Negative electrospray ionization of iron(III) salen complex of flavonoids, M, was used in conjunction with collision-induced dissociation (CID) to examine the formation and subsequent fragmentation reactions of their radical anions [M-2H]•- Sixteen different flavonoids were investigated from three different sub-groups (flavanone, flavone and flavanol). All formed the desired iron salen complex, [FeIII(salen)(M-2H)]-•, and all but one of these complexes produced the radical anion upon CID. The CID fragmentation reactions of these radical anions, [M-2H]-•, were compared to their even electron counterparts [M-H]-•. Generally the former provided more structural information, with novel cross-ring..