Indole → 3-bromo-4-(1H-indol-3-yl)-1-phenyl-pyrrole-2,5-dione

Participants

Reaction Steps

(±)-Trans-3-(5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-1-yl)-4(1H-indol-3-yl)pyrrolidine-2,5-dione may be prepared by reacting 1H-indole and 3,4-dibromo-1-phenyl-pyrrole-2,5-dione in the presence of methyl magnesium bromide to yield 3-bromo-4-(1H-indol-3-yl)-1-phenyl-pyrrole-2,5-dione. The 3-bromo-4-(1H-indol-3-yl)-1-phenyl-pyrrole-2,5-dione is subsequently reacted with 5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinoline and LiHMDS (lithium hexamethyldisilane) in toluene or (5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-1-yl)-boranediol and Pd(PPh3)4 (tetrakis(triphenylphosphine)palladium) to yield 3-(5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-1-yl)-4-(1H-indol-3-yl)-1-phenyl-pyrrole-2,5-dione, which is reduced and deprotected by treatment with Mg in methanol, as in Example 2 procedure C, followed by catalytic hydrogenation over palladium on carbon to yield (±)-trans-3-(5,6-dihydro-4H-pyrrolo[3,2,1-ij]quinolin-1-yl)-4(1H-indol-3-yl)pyrrolidine-2,5-dione. Bnz is benzyl.

Provenance & Evidence