Methanol → (E)-2-(6-fluoro-2-hydroxy-1-indanylidene)acetamide

Participants

Reaction Steps

A solution of (Z)-2-(6-fluoro-2-hydroxy-1-indanylidene)acetamide (5.456 g, 0.026 mol) in dichloromethane:methanol/9:1 (1000 ml) was irradiated by an Canrad-Hanovia quartz, mecury-vapor photochemical immersion lamp, 450 wattts (Ace Glass, 7825-35) for 1h. The volitiles were removed by spin evaporation in vacuo to give a light brown solid residue. This residue was chromatographed on Silica Gel 60 using a step gradient going from ethyl acetate:hexanes/1:1 to ethyl acetate:ethanol/1:1. Fractions containing (E)-2-(6-fluoro-2-hydroxy-1-indanylidene)acetamide were combined and concentrated by spin evaporation in vacuo. The resulting residue was recrystallized from ethanol-hexanes to give 1.31 g (24%) of (E)-2-(6-fluoro-2-hydroxy-1-indanylidene)acetamide as an off-white crystalline solid, m.p., 159°-163° C., NMR(DMSO-d6): d 8.56 (dd, 1H, JHF =11.0 Hz, JHH =2.9 Hz), 7.67 (br s, 1H), 7.34-7.30 (m, 1H), 7.2-7.13 (m, 1H), 7.06 (br s, 1H),6.18 (s, 1H), 5.69 (d, 1H, J=6.8 Hz), 4.74 (q, 1H, J=12.1 Hz, J=6.0 Hz), 3.21-3.13 (m, 1H) 2.73-2.66(m, 1H); steady state nOe: irradiation at d6.19, observed 5.4% nOe at d4.74, 4.3% at d7.67 and 1.5% at d 5.69.

Provenance & Evidence