Diethyl Oxalate → HCID 13457890, compound

Participants

Reaction Steps

To a stirred solution of cis-1,2,3,4-tetrahydro-1-methylaminomethyl-4-phenylisoquinoline dihydrochloride (30.6 g, 0.094 m) in chloroform (500 ml) maintained under nitrogen at ambient temperature was added triethylamine (42.6 g, 0.42 m) and then in one portion diethyloxalate (30.1 g, 0.206 m) and the mixture heated to reflux for 4 hours. The mixture was cooled and washed with 10% HCl (3×150 ml) and water (150 ml), then dried over MgSO4. The solvent was evaporated to give 22.3 g of cis-1,3,4,6,7,11b-hexahydro-2-methyl-7-phenyl-2H-pyrazino[2,1-a]isoquinoline-3,4-dione as a pale yellow solid. An analytical sample, recrystallized from isopropanol, had m.p. 193°-194°.

Provenance & Evidence