Benzotriazol-1-yloxy-tris(dimethylamino)phosphonium hexafluorophosphate → (S)-2-Ethanesulfonylamino-N-(2-{4-[2-(4-fluoro-phenoxy)-ethoxy]-3-methoxy-phenyl}-ethyl)-3-methyl-butyramide

Participants

Reaction Steps

To a mixture of (S)-2-ethanesulfonylamino-3-methyl-butyric acid (0.63 g), 2-{4-[2-(4-fluoro-phenoxy)-ethoxy]-3-methoxy-phenyl}-ethylamine hydrochloride (1.0 g) and diethyl-isopropylamine (1.8 ml) in dimethylformamide (30 ml) is added benzotriazol-1-yloxy-tris-(dimethylamino)phosphonium hexafluorophosphate (1.5 g) in one portion. The reaction mixture is stirred for 2 hours at room temperature. Water (200 ml) is then added. The mixture is extracted with ethyl acetate (2×200 ml). The organic layers are washed with brine (2×200 ml), dried (MgSO4) and evaporated. The residue is purified by flash column chromatography on silica gel (ethyl acetate/hexane 2:1) and recrystallisation (ethyl acetate/hexane). (S)-2-Ethanesulfonylamino-N-(2-{4-[2-(4-fluoro-phenoxy)-ethoxy]-3-methoxy-phenyl}-ethyl)-3-methyl-butyramide is obtained, m.p. 124-125° C.

Provenance & Evidence