Pyridine → rac-(2'S,3'R,4'S,5'R)-2'-(3-acetoxy-2,2-dimethyl-propyl)-6-chloro-4'-(3-chloro-2-fluoro-phenyl)-2-oxo-1,2-dihydro-spiro[indole-3,3'-pyrrolidine]-5'-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To a solution of rac-(2′S,3′R,4′S,5′R)-6-chloro-4′-(3-chloro-2-fluoro-phenyl)-2′-(3-hydroxy-2,2-dimethyl-propyl)-2-oxo-1,2-dihydro-spiro[indole-3,3′-pyrrolidine]-5′-carboxylic acid tert-butyl ester (0.3 g, 0.56 mmol) in tetrahydrofuran (2 mL) at 0° C. was added pyridine (44 mg, 0.56 mmol) and acetyl chloride (44 mg, 0.56 mmol). The mixture was stirred at room temperature for 1 h. The mixture was concentrated, and the residue was partitioned between ethyl acetate and water. The organic layer was separated, washed with water, saturated aqueous CuSO4, brine, dried over MgSO4, and concentrated to give as rac-(2′S,3′R,4′S,5′R)-2′-(3-acetoxy-2,2-dimethyl-propyl)-6-chloro-4′-(3-chloro-2-fluoro-phenyl)-2-oxo-1,2-dihydro-spiro[indole-3,3′-pyrrolidine]-5′-carboxylic acid tert-butyl ester as a yellow oil (0.24 g, 74%)

Provenance & Evidence