反应详情

To a suspension of 2-(1-methyl-2-oxo-propyloxy)-5-iodobenzyltriphenylphosphonium bromide (0.71 g, 0.00108 mol) in absolute ethanol (3 ml) was added dropwise at room temperature a solution of sodium (0.025 g) in absolute ethanol (1 ml). After twelve hours at room temperature, diethyl ether and water were added. The organic phase was separated, dried and evaporated. The residue was chromatographed on silica gel, eluting with a mixture of dichloromethane/heptane (50/50) to give 0.29 g (85%) of 6-iodo-2,2,3-trimethyl-1(2H)-benzopyran, as an oil, 1NMR (CDCl3): δ1.4 (s, 6H), 1.8 (s, 3H), 6.0 (s, 1H), 6.55 (d, 1H), 7.2 (d, 1H), 7.35 (d, 1H).

1. waitAfter twelve hours at room temperature
2. customThe organic phase was separated
3. customdried
4. customevaporated
5. customThe residue was chromatographed on silica gel
6. washeluting with a mixture of dichloromethane/heptane (50/50)