A radical approach to araliopsine and related quinoline alkaloids using manganese(III) acetate

Reaction of 4-hydroxy-1-methyl-2(1H)-quinolone 3 with electron-rich alkenes and manganese(III) acetate produces tricyclic quinoline alkaloids, including araliopsine 1, in one-pot reactions. This combined intermolecular addition–cyclisation reaction produces angular and/or linear tricycles and the regioselectivity of the cyclisation is shown to depend on whether alkyl or aryl substituents are attached to the alkene.