反应详情

To a stirred solution of 2-Bromo-7-acetoxy-3-(3,4,5-trimethoxybenzoyl)-6-methoxybenzofuran (50 mg, 0.10 mmol) in dichloromethane (1 ml) and triethylamine (0.5 ml) was added Pd(Ph3P)2Cl2 (3.5 mg, 5 mol %) and the reaction vessel was evacuated and backfilled with nitrogen three times. Trimethylsilylacetylene (30 mg, 0.30 mmol) and copper (I) iodide (3 mg, 15 mol %) were added sequentially and the resulting dark mixture was stirred for two hours at room temperature. After this time the reaction was concentrated under vacuum and treated with methanol (1 ml) and potassium hydroxide (30 mg, excess). Stirring was continued for 0.5 hours then the crude mixture was concentrated onto silica and chromatographed (silica gel, gradient elution—2:1 hexanes:ethyl acetate, 1:1 hexanes:ethyl acetate) to afford the product as a tan solid (10 mg, 26%); 1H NMR (CDCl3) δ 7.26 (d, J=8.6 Hz, 1H), 7.20 (s, 2H), 6.98 (d, J=8.6 Hz, 1H), 3.96 (s, 3H), 3.93 (s, 3H), 3.87 (s, 6H), 3.51 (s, 1H); LRMS (ESI) m/z=383 (M+H+).

1. customthe reaction vessel was evacuated
2. concentrationAfter this time the reaction was concentrated under vacuum
3. additiontreated with methanol (1 ml) and potassium hydroxide (30 mg, excess)
4. stirringStirring
5. waitwas continued for 0.5 hours
6. concentrationthe crude mixture was concentrated onto silica
7. customchromatographed (silica gel, gradient elution—2:1 hexanes:ethyl acetate, 1:1 hexanes:ethyl acetate)