1-(2-Methoxyphenyl)piperazine → 1-(2-Methoxyphenyl)-4-methylpiperazine

Participants

Reaction Steps

To an ice-cooled, stirred suspension of lithium aluminium hydride (7.9 g, 0.21 mol) in dry tetrahydrofuran (1 50 ml) was added a solution of 1-(2-methoxyphenyl) piperazine (10 g, 52 mmol) in dry tetrahydrofuran (150 ml) over 0.5 h under argon. A solution of ethyl formate (12.6 ml, 0.156 mol) in dry tetrahydrofuran (25 ml) was added to the cold mixture over 0.25 h and the resulting suspension was stirred for a further 2 h at room temperature. Dilute sodium hydroxide solution (15%, 8 ml) was slowly added to the cooled mixture, followed by water (24 ml) and the whole left to stir for 0.25 h. The mixture was filtered and the filtrate concentrated to an oil which was partitioned between dichloromethane and water. The organic phase was dried and concentrated to an oil which was purified by column chromatography on silica gel eluting with a methanol/dichloromethane gradient to afford the title compound as a colourless oil (5.7 g, 53%)

Provenance & Evidence