反应详情

To a solution of 0.200 g (0.855 mmol) 4-hydroxymethyl-3-methylbenzofuran-2-carboxylic acid ethyl ester (Example 92, Step 2) in 5 mL of THF was added 0.336 g (1.28 mmol) of triphenylphosphine and 0.355 g (1.07 mmol) of carbon tetrabromide. The reaction was stirred at room temperature for 1 h and then concentrated in vacuo. The residue was diluted ith 20 mL of ether and filtered. The filtrate was concentrated in vacuo and chromatographed on silica gel eluting with ethyl acetate/hexanes (1:10) to provide 0.196 g of 4-bromomethyl-3-methylbenzofuran-2-carboxylic acid ethyl ester.

1. concentrationconcentrated in vacuo
2. additionThe residue was diluted ith 20 mL of ether
3. filtrationfiltered
4. concentrationThe filtrate was concentrated in vacuo
5. customchromatographed on silica gel eluting with ethyl acetate/hexanes (1:10)