Potassium Carbonate → Spiro[cyclohexane-1,3'-indolin]-2'-one

Participants

Reaction Steps

To a solution of 5′-bromospiro[cyclohexane-1,3′-[3H]indol]-2′(1′H)-one (1.00 g, 3.57 mmol) in dimethoxyethane (20 cm3) was added tetrakis(triphenylphosphine)palladium (0.20 g, 0.17 mmol) under nitrogen. After 15 min. 3-formylphenylboronic acid (1.00 g, 6.93 g) was added followed by potassium carbonate (2.90 g, 21 mmol) in water (10 cm3). After 20 h at reflux, the mixture was cooled poured into water and extracted with EtOAc (×3). The combined organic extract was washed with sat. brine, dried (MgSO4) and evaporated. The residue was purified by column chromatography (SiO2, EtOAc: hexane, gradient elution) to afford the title compound (0.66 g, 2.15 mmol, 60%) as a white solid, 1H NMR (CDCl3) δ 1.65-1.85 (m, 6H), 1.86-2.08 (m, 4H), 7.22 (d, 1H, J=8 Hz), 7.48 (dd, 1Hz), J=8, 2 Hz), 7.61 (t, 1H, J=8 Hz), 7.66 (d, 1H, J=2 Hz), 7.81-7.88 (m, 2H), 8.06 (t, 1H, J=2 Hz), 8.30 (s, 1H, br); MS ((+)ESI) m/z 306 (M+H)+.

Provenance & Evidence