Hydrochloric Acid → 2,2-Dimethyl-propionic acid 3-(4'-chloro-6-fluoro-4-methyl-biphenyl-3-yl)-8-methoxy-2-oxo-1,8-diaza-spiro[4.5]dec-3-en-4-yl ester

Participants

Reaction Steps

To a solution of 3-(4′-chloro-6-fluoro-4-methyl-biphenyl-3-yl)-4-hydroxy-8-methoxy-1,8-diaza-spiro[4.5]dec-3-en-2-one (170 mg) and pivaloyl chloride (98 mg) in acetonitrile (5 ml) is added pyridine (64 mg) and the reaction mixture stirred at room temperature for 8 hours. The mixture is poured on diluted HCl and extracted with ethyl acetate (3×). The combined organic layers are washed with brine, dried over sodium sulfate and concentrated. The residue is triturated with heptane, filtered and dried. Yield: 100 mg of 2,2-dimethyl-propionic acid 3-(4′-chloro-6-fluoro-4-methyl-biphenyl-3-yl)-8-methoxy-2-oxo-1,8-diaza-spiro[4.5]dec-3-en-4-yl ester as a solid, mp: 150-151° C.

Provenance & Evidence