4-Hydroxypyrrolidine → 4-[(3-hydroxypyrrolidin-1-yl)methyl]-1-(phenylsulfonyl)-1H-indol-5-ol

Participants

Reaction Steps

To a solution of 5-(benzyloxy)-1-(phenylsulfonyl)-1H-indole-4-carbaldehyde (Intermediate 4, 100 mg, 0.250 mmol) in DCE (3 mL) was added 3-hydroxypyrrolidine, (33 mg, 0.38 mmol) and sodium triacetoxyborohydride (0.16 g, 0.77 mmol) and the mixture was stirred at room temperature overnight. The solvent was removed under reduced pressure and the residue was dissolved in MeOH (2 mL) and Pd/C 10 wt. % (0.020 g, 0.019 mmol) was added and the mixture was flushed with N2 gas. Ammonium formate (0.050 g, 0.80 mmol) was added and the reaction mixture was stirred at room temperature overnight. The solvent was removed under reduced pressure and the residue was taken up in CHCl3/H2O, and the mixture was washed with water and brine, dried (MgSO4) and the solvent was removed under reduced pressure to give 4-[(3-hydroxypyrrolidin-1-yl)methyl]-1-(phenylsulfonyl)-1H-indol-5-ol (85 mg) as an oil. MS m/z 373 [M+H]+.

Provenance & Evidence