Trifluoroacetic acid → HCID 68761279, compound

Participants

Reaction Conditions

Reaction Steps

Tert-butyl 2-benzyl-4-(methoxymethylene)piperidine-1-carboxylate (274 mg, 0.86 mmol) and (4-chlorophenyl)hydrazine hydrochloride (186 mg, 1.04 mmol) were dissolved in chloroform (10 mL) and then TFA (1.0 mL, 12.98 mmol) was added. The resulting mixture was heated to reflux for 8 h at which time it was cooled to ambient and then quenched by the slow addition of saturated sodium bicarbonate solution. The reaction mixture was dissolved in EtOAc and then washed twice with water and once with brine. The organic portion was dried over magnesium sulfate, filtered and concentrated. The residue was dissolved in dichloromethane (10 mL) and cooled to 0° C. Triethylamine (0.24 mL, 1.73 mmol) was added followed by boc anhydride (189 mg, 0.86 mmol). The resulting solution was warmed ambient and stirred at this temperature for 12 h. At this time, it was taken up in EtOAc and washed twice with water and once with brine. The organic layer was dried over magnesium sulfate, filtered and concentrated. The residue thus obtained was purified via silica gel chromatography to give tert-butyl 2′-benzyl-5-chlorospiro[indole-3,4′-piperidine]-1′-carboxylate as a mixture of diastereomers (220 mg, 62%). LCMS (APCI+) m/z 411.1 [M+H]+; Rt=4.56, 4.63 min.

Provenance & Evidence