1H-Indole-6-carboxaldehyde → Indole

Participants

Reaction Steps

To a stirred solution of 1H-indole-6-carbaldehyde (99 mg, 0.68 mmol) and tert-butyl (1S,2R)-3-amino-1-(3,5-difluorobenzyl)-2-hydroxypropylcarbamate acetate 3 (256 mg, 0.68 mmol) in 2-propanol (3 mL) was added sodium borohydride (30 mg, 0.82 mmol). The reaction mixture was stirred for 12 h., quenched with methanol, and concentrated under reduced pressure. Purification by flash column chromatography (silica, 1:1 ethyl acetate/hexanes) provided indole (50 mg): 1H NMR (300 MHz, CDCl3) δ 8.41 (br s, 1H), 7.60 (d, J=8 Hz, 1H), 7.38 (s, 1H), 7.21 (t, J=3 Hz, 1H), 7.04 (dd, J=8, 1 Hz, 1H), 6.71–6.73 (m, 3H), 6.61–6.68 (m, 1H), 6.53 (s, 1H), 5.38 (br s, 2H), 4.66 (d, J=9 Hz, 1H), 3.89 (s, 2H), 3.49–3.54 (m, 1H), 2.91–2.98 (m, 1H), 2.62–2.73 (m, 3H), 1.35 (s, 9H).

Provenance & Evidence