Formaldehyde → 3-(6-hydroxy-1,3-benzodioxol-5-yl)-3-(hydroxymethyl)-1-pentyl-1,3-dihydro-2H-pyrrolo[2,3-b]pyridin-2-one

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-(6-hydroxy-1,3-benzodioxol-5-yl)-1-pentyl-1,3-dihydro-2H-pyrrolo[2,3-b]pyridin-2-one (2.75 g, 8.08 mmol) in anhydrous dichloromethane (40.0 mL) were added triethylamine (4.91 g, 48.5 mmol) and chlorotrimethylsilane (3.51 g, 32.3 mmol) under nitrogen at 0° C. The reaction mixture was stirred at 0° C. for 2 h and diluted with anhydrous dichloromethane (50.0 mL). The organic layer was washed with water (2×25.0 mL), dried over magnesium sulfate and filtered. The filtrate was concentrated in vacuo to dryness. The gummy brown residue was dissolved in THF (40.0 mL) followed by the addition of formaldehyde solution (2.20 mL, 80.8 mmol, 37 wt % in water) and ytterbium (III) trifluoromethanesulfonate (1.25 g, 2.02 mmol). The reaction mixture was stirred at ambient temperature for 36 h and diluted with dichloromethane (100 mL). The organic layer was washed with saturated NaHCO3 (50.0 mL), saturated ammonium chloride (50.0 mL) and water (50.0 mL), dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated in vacuo to dryness to afford the title compound (2.85 g, 98%): 1H NMR (300 MHz, CDCl3) δ 10.02 (s, 1H), 8.29 (dd, 1H), 7.72 (dd, 1H), 7.13 (dd, 1H), 6.55 (s, 1H), 6.46 (s, 1H), 5.86 (dd, 2H), 4.37 (dd, 2H), 3.77-3.84 (m, 2H), 3.25 (br, 1H), 1.63-1.77 (m, 2H), 1.36-1.22 (m, 4H), 0.85 (t, 3H); 13C NMR (75 MHz, CDCl3) δ 179.9, 156.6, 152.3, 148.4, 147.5, 141.5, 133.8, 124.3, 118.7, 111.3, 107.9, 101.9, 101.4, 64.3, 59.1, 39.9, 31.6, 27.2, 22.3, 13.9; MS (ES+) m/z 371.1 (M+1).

Provenance & Evidence