Methyl iodide → 4-(3-Benzyl-5-methyl-2-methylcarbamoyl-benzofuran-7-yl)-piperazine-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

4-(3-Benzyl-2-carbamoyl-5-methyl-benzofuran-7-yl)-piperazine-1-carboxylic acid tert-butyl ester (0.25 gm, 0.556 mmol) was dissolved in 5 ml DMF and sodium hydride (60% in oil, 0.033 gm, 0.83 mmol) was added, resulting in formation of a precipitate. Methyl iodide (0.052 ml, 0.83 mmol) was added and the solid dissolved to give a clear solution. After one hour the mixture was concentrated under reduced pressure and the residue was purified by preparative thin layer chromatography (3/97 methanol/dichloromethane). One band was again purified (40/60, tetrahydrofuran/hexane) to give 4-(3-Benzyl-5-methyl-2-methylcarbamoyl-benzofuran-7-yl)-piperazine-1-carboxylic acid tert-butyl ester. A second band was recrystallized from acetonitrile to give 4-(3-Benzyl-2-dimethylcarbamoyl-5-methyl-benzofuran-7-yl)-piperazine-1-carboxylic acid tert-butyl ester.

Provenance & Evidence