2-Methoxyethylamine → tert-Butyl 4-[(2-methoxyethyl)amino]piperidine-1-carboxylate

Participants

Reaction Steps

1-BOC-4-piperidone (2.00 g) and 2-methoxyethylamine (872 μl) were stirred together in methanol (20 ml) at room temperature for 12 hours. Sodium borohydride (760 mg) was added in several aliquots over 30 minutes and the reaction mixture stirred for a further 12 hours at ambient temperature. The solvents were removed in vacuo and the residue diluted with dichloromethane (50 ml) and washed with brine, dried (MgSO4). The solvents were removed in vacuo to give a residue which was purified by flash silica chromatography to give 4-(2-methoxy-ethylamino)-piperidine-1-carboxylic acid tert-butyl ester (1.69 g) as a colourless oil. To a solution of 4-(2-methoxy-ethylamino)-piperidine-1-carboxylic acid tert-butyl ester (425 mg) stirring in anhydrous acetonitrile (10 ml) was added benzyl bromide (215 μl), followed by potassium carbonate (340 mg) and the reaction mixture heated to reflux for 12 hours.

Provenance & Evidence