Ethyl Acetate → 2,3-dihydrospiro[furo[3,2-f][1,4]benzodioxine-9,3'-indol]-2'(1'H)-one

Participants

Reaction Conditions

Reaction Steps

6-chloro-1′-(diphenylmethyl)-2,3-dihydrospiro[furo[3,2-f][1,4]benzodioxine-9,3′-indol]-2′(1′H)-one (2.1 g, 4.24 mmol) was suspended in methanol (20 mL) and ethyl acetate (80 mL) in a steel bomb and palladium on carbon (20% w/w, 0.45 g) was added. The bomb was pressurized with hydrogen gas (120 psi) and the mixture was stirred at 60° C. for 16 h. The reaction mixture was allowed to cool to ambient temperature and filtered through a pad of diatomaceous earth. The filtrate was concentrated in vacuo and the residue triturated with ethyl acetate to afford 2,3-dihydrospiro[furo[3,2-f][1,4]benzodioxine-9,3′-indol]-2′(1′H)-one (0.522 g, 42%) as a colorless solid: mp 259-261° C.; 1H NMR (300 MHz, CD3OD) δ7.27-7.18 (m, 1H), 7.09-6.88 (m, 3H), 6.70 (d, J=8.7 Hz, 1H), 6.39 (d, J=8.7 Hz, 1H), 4.75 (d, J=9.3 Hz, 1H), 4.59 (d, J=9.0 Hz, 1H), 4.12-3.90 (m, 4H); 13C NMR (75 MHz, CD3OD) δ 181.0, 157.5, 142.4, 141.3, 139.6, 133.9, 129.8, 124.5, 124.0, 119.0, 117.1, 111.0, 102.9, 82.4, 66.0, 65.2, 59.1; MS (ES+) m/z 296.2 (M+1).

Provenance & Evidence