(E)-2-(6-fluoro-1-indanylidene)acetamide → (Z)-2-(6-fluoro-1-indanylidene)acetamide

Participants

Reaction Steps

A solution of (E)-2-(6-fluoro-1-indanylidene)acetamide (20 g, 104.6 mmol) in dichloromethane:methanol (3:1) (1000 ml) was irradiated by an Canrad-Hanovia quartz, mercury-vapor photochemical immersion lamp, 450 watts (Ace Glass, 7825-35) for 0.5 h. The volatiles were removed by spin evaporation in vacuo to give a beige 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 (Z)-2-(6-fluoro-1-indanylidene)acetamide were combined and concentrated by spin evaporation in vacuo. The resulting solid was slurried in hexanes to give 7.52 g (37%) of (Z)-2-(6-fluoro-1-indanylidene)acetamide as a white crystalline solid, m.p., 175-177° C.:

Provenance & Evidence