Methanol → Methyl 1-acetyl-4-methoxyindoline-7-acetate

Participants

Reaction Steps

Thallium(III) nitrate trihydrate (3.21 g, 7.1 mmol) was added to a solution of 1,7-diacetyl-4-methoxyindoline 22 (1.65 g, 7.1 mmol) in MeOH (70 ml) containing perchloric acid (60% w/w, 1.5 ml) and the mixture was stirred at rt for 4 h. The precipitated white solid was filtered off and the filtrate was concentrated to about 10 ml, diluted with EtOAc (50 ml) and washed with water. The aqueous phase was extracted with EtOAc and the combined organic phases were washed with saturated aq. NaHCO3 and brine, dried and evaporated to give a viscous oil. Flash chromatography [EtOAc-hexanes (4:1)] afforded 23 as white crystals (0.88 g, 47%), mp 80-81° C. (from EtOAc-hexanes) (Found: C, 63.60; H, 6.50; N, 5.28. C14H17NO4 requires C, 63.87; H, 5.51; N, 5.32%); δH (90 MHz) 7.04 (1 H, d, J 8.3, H-5), 6.63 (1 H, d, H-6), 4.06 (2 H, t, J 8.1, H-2), 3.81 (3 H, s, OMe), 3.76 (2 H, s, ArCH2), 3.71 (3 H, s, CO2Me), 2.96 (2 H, t, 3-H) and 2.24 (3 H, s, N-Ac).

Provenance & Evidence