Sodium borohydride → (+/-)-Ethyl (4-amino-3-methyl-2,3-dihydro-1H-indol-3-yl)acetate

Participants

Reaction Steps

To a solution of (±)-ethyl (3-methyl-4-nitro-2-thioxo-2,3-dihydro-1H-indol-3-yl)acetate from Step A (3.65 g, 12.4 mmol) and nickel (H) chloride hexahydrate (23.6 g, 99.2 mmol) in MeOH (30 mL) and THF (30 mL), at 0° C., was added NaBH4 (11.3 g, 298 mmol) in portions, over 1 h. The resulting mixture was stirred for 10 min, then filtered through a pad of Celite, washing with MeOH, and the filtrate was concentrated in vacuo. The residue was purified by silica gel chromatography, eluting with CH2Cl2:MeOH—90:10, to give the title compound. MS: m/z=235 (M+1).

Provenance & Evidence