Potassium Carbonate → HCID 69823126, compound

Participants

Reaction Steps

2 ml of 1N NaOH solution were added to a solution of 0.726 g (1.87 mmol) of methyl trans-[3-(4-bromo-3,5-dimethoxy-phenyl)-1-methyl-piperidin-4-yl]-acetate in 3 ml of ethanol and the mixture was stirred at 50° for 30 minutes. The solution was evaporated and the residue was dried in a high vacuum. The thus-obtained sodium salt was suspended in 5 ml of acetonitrile. After the addition of 278 mg (2 mmol) of potassium carbonate the suspension was treated at 0° with 0.913 ml (10 mmol) of phosphorus oxychloride and the mixture was subsequently stirred at 50° for 2 hours. Subsequently, the mixture was poured into 10 ml of water, adjusted to pH=12 with 28% NaOH and extracted three times with 15 ml of ethyl acetate. The organic phase was dried (Na2SO4), filtered and evaporated. Chromatography (silica gel, methylene chloride/methanol 95:5) yielded 0.385 g (58%) of trans-8-bromo-7,9-dimethoxy-2-methyl-1,3,4,4a,5,10b-hexahydro-2H-benzo[h]isoquinolin-6-one, which was converted with HCl in methanol into the hydrochloride with m.p. 226-228°.

Provenance & Evidence