1,1'-Carbonyldiimidazole → 3,4,4a,5-tetrahydro-5-methylpyrimido-[1,6-a]indol-1(2H)-one

Participants

Reaction Conditions

Reaction Steps

To a solution of crude 2-(2,3-dihydro-3-methylindol-2-yl)ethylamine (1.75 g) in tetrahydrofuran (12 ml) at room temperature was added in small portions 1,1'-carbonyldiimidazole (1.1 g). After being stirred for 2 hours, the reaction mixture was evaporated in vacuo. The oil obtained was dissolved in toluene (25 ml) and the solution was heated at 110° C. for 1.5 hours. After evaporation of the solvent, the residue was purified by silica gel column chromatography (1% methanol-chloroform) to give crystals. Recrystallization from chloroform-ethyl acetate-hexane gave 3,4,4a,5-tetrahydro-5-methylpyrimido-[1,6-a]indol-1(2H)-one (0.65 g).

Provenance & Evidence