An investigation of the allylation cascade reactions of substituted indigos.

ABSTRACT: In a continuation of the exploration of indigo cascade reactions, a series of -OMe, -Ph, -Br and -NO₂ substituted indigos 1a-i were synthesised to probe electronic effects upon the outcome of allylation cascade reactions. When indigos 1a-i in the presence of base were reacted with allyl bromide, spiroindolinepyridoindolones 17-25 (36-75%) were obtained as the major products in each case, marking a shift in outcome relative to that previously reported for unsubstituted indigo. In electron-rich derivatives (-OMe, -Ph), C-allylspiroindolinepyridoindolediones 26-29 (3-11%) were also isolated, which are most likely formed via a Claisen rearrangement of the respective spiroindolinepyridoindolones 18-21. Additionally, the isolation of diallylbiindolone 16, oxazinobiindole

SUBMITTER: Perry MJ 

PROVIDER: S-EPMC9901421 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature