Methyl 4-Formylbenzoate → Methyl 4-((4-methylpiperazin-1-yl)methyl)benzoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of 4-formyl-benzoic acid methyl ester (10.0 g, 61 mmol) in methanol (100 ml) is treated sequentially with 1-methylpiperazine (6.7 g, 67 mmol) and platinum (5%) on sulfided carbon (0.5 g). The resulting solution is then heated at 90° C. and is subjected to a pressure of 5 bar of hydrogen for a period of 4 hrs until the hydrogen uptake is complete. The reaction mixture is cooled to room temperature and filtrated over a pad of Celite. The methanol is removed under reduced pressure and replaced with toluene (100 ml). The resulting organic solution is extracted with aqueous HCl (2N, 2×50 ml). The aqueous layer is treated with concentrated aqueous NaOH (30%) to set the pH to 12 and is back-extracted with toluene (2×50 ml). The combined organic layers are concentrated in vacuo to give 12.9 g (85%) of 4-(4-methyl-piperazin-1-ylmethyl)-benzoic acid methyl ester as a pale yellow oil which may be further purified by distillation under reduced pressure.

Herkunft & Nachweise