反应详情

温度

-78 °C

To a solution of 2,4-bis(methoxymethoxy)-1-methyl-benzene (Intermediate 7, 5.5 g, 25.94 mmol) in dry tetrahydrofuran (50 ml) at room temperature BuLi 1.6M in hexane (19.45 ml, 31.13 mmol) was added and the reaction mixture was stirred for 30 minutes at the same temperature. The mixture was cooled to −78° C. and it was added (via cannulation) to a solution of ethyl chlorooxoacetate (4.35 ml, 38.9 mmol) in dry tetrahydrofuran (30 ml) at −78° C. The reaction mixture was stirred at −78° C. for 30 minutes. The reaction was quenched with water (20 ml), diluted with brine (50 ml) and extracted with ethyl acetate (2×100 ml). Combined organic layers were dried over sodium sulphate, filtered and evaporated. The residue was purified by flash chromatography (Biotage system) on silica gel using a 100 g SNAP column and cyclohexane to cyclohexane/ethyl acetate 8:2 as eluent affording the title compound (4.65 g) as a light yellow oil.

1. stirringThe reaction mixture was stirred at −78° C. for 30 minutes
2. customThe reaction was quenched with water (20 ml)
3. additiondiluted with brine (50 ml)
4. extractionextracted with ethyl acetate (2×100 ml)
5. dry with materialCombined organic layers were dried over sodium sulphate
6. filtrationfiltered
7. customevaporated
8. customThe residue was purified by flash chromatography (Biotage system) on silica gel using a 100 g SNAP column and cyclohexane to cyclohexane/ethyl acetate 8:2 as eluent