反应详情

The solution of crude 4-bromo-2,2-dimethyl-5-oxo-1,3-dioxolane-4-acetic acid, tert-butyldimethylsilyl ester (72.4 mmol) in carbon tetrachloride (˜220 ml) was cooled to 0-5° C. and treated dropwise over 10 minutes and under good stirring with a solution of 1,8-diazabicyclo (5,4,0) undec-7-ene (12.1 g, 79.6 mmol) in dry tetrahydrofuran (125 ml). A heavy precipitate was formed which gradually became a granular solid. After 1 h, the solid obtained was filtered and washed with a small amount of tetrahydrofuran. The filtrate was concentrated under reduced pressure to give a light orange oil which was used as such for the next step.

1. additiontreated dropwise over 10 minutes
2. customA heavy precipitate was formed which
3. customthe solid obtained
4. filtrationwas filtered
5. washwashed with a small amount of tetrahydrofuran
6. concentrationThe filtrate was concentrated under reduced pressure
7. customto give a light orange oil which