Hydrazine, (4-chlorophenyl)-, hydrochloride (1:1) → (RS,SR)-benzenesulfonyl-(6-chloro-2,3,4,9-tetrahydro-1H-carbazol-2-yl)-fluoro-acetic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

To 1.70 g (5.2 mmol) (RS,SR)-benzenesulfonyl-fluoro-(3-oxo-cyclohexyl)-acetic acid methyl ester in glacial acetic acid (20 mL), 1.05 g (5.72 mmol, 1.1 eq) of (4-chloro-phenyl)-hydrazine hydrochloride were added and the reaction mixture was stirred at 40° C. over night. An aqueous solution of NaHCO3 was added until pH=7 was reached, and the mixture was extracted with EtOAc. The combined organic phases were dried over Na2SO4, filtered and evaporated. A column chromatography on silica gel with heptane/EtOAc 2:1 followed by a trituration from Et2O yielded 1.56 g (70%) of (RS,SR)-benzenesulfonyl-(6-chloro-2,3,4,9-tetrahydro-1H-carbazol-2-yl)-fluoro-acetic acid methyl ester as a white solid, MS: 436 (MH+).

Provenance & Evidence