反应详情

A solution of (8-thiocyanato-chroman-5-yloxy)-acetic acid methyl ester (1.3 g, 4.6 mmol), dithiothreitol (910 mg, 6 mmol), and KH2PO4 (4.6 mL of a 0.02M solution) in 30 mL MeOH was heated at reflux for 1 hour after which time the reaction was cooled and concentrated in vacuo. Purification by flash column chromatography (gradient elution: 10% EtOAc/hexanes to 35% EtOAc/hexanes) gave the title compound (710 mg, 61%) as a pale yellow solid. 400 MHz 1H NMR (DMSO-d6) δ 6.97 (d, 1H, J=8.5 Hz), 6.31 (d, 1H, J=8.5 Hz), 4.70 (s, 2H), 4.40 (s, 1H), 4.11 (t, 2H, J=5.4 Hz), 3.63 (s, 3H), 2.56 (t, 2H, J=6.3 Hz), 1.84 (m, 2H).; MS m/z 255 (M+1).

1. temperatureat reflux for 1 hour after which time the reaction
2. temperaturewas cooled
3. concentrationconcentrated in vacuo
4. customPurification
5. washby flash column chromatography (gradient elution: 10% EtOAc/hexanes to 35% EtOAc/hexanes)