3-Methoxytyramine → (S)-2-(Ethylsulfonylamino)-3-methyl-butyric acid N-[2-(4-hydroxy-3-methoxyphenyl)-ethyl]-amide

Participants

Reaction Steps

1.7 g of 2-(4-hydroxy-3-methoxy-phenyl)-ethylamine and 2.1 g of (S)-2-(ethylsulfonylamino)-3-methyl-butyric acid are stirred at room temperature for 2 hours together with 4.6 g of (benzotriazol-1-yl)-tris(dimethylamino)phosphonium hexafluorophosphate and 4.5 ml of diisopropylethylamine in 40 ml of dimethylformamide. The reaction mixture is then introduced into 600 ml of water. Extraction is carried out twice using 400 ml of ethyl acetate each time. The organic phases are washed twice using 300 ml of water each time and once with 200 ml of saturated sodium chloride solution, dried over magnesium sulfate and concentrated, yielding (S)-2-(ethylsulfonylamino)3-methyl-butyric acid N-[2-(4-hydroxy-3-methoxyphenyl)-ethyl]-amide in the form of a brown oil, which can be purified by chromatography on silica gel with ethyl acetate.

Provenance & Evidence