反应详情

A solution of 2.8 g of the compound obtained in EXAMPLE 16 in 10 ml of pyridine is cooled in an ice bath and 0.51 ml of acetyl chloride is added. The reaction medium is stirred for 3 hours at RT and poured into water. It is extracted with AcOEt, washed with water and with a 5% solution of potassium hydrogensulfate, dried over sodium sulfate and evaporated under vacuum. The residue is taken up with DCM and the precipitate formed is filtered off to give 2.8 g of the expected product, a sample of which is crystallized from an MeOH/iso ether mixture. M.p.=205°-210° C.

1. extractionIt is extracted with AcOEt
2. washwashed with water and with a 5% solution of potassium hydrogensulfate
3. dry with materialdried over sodium sulfate
4. customevaporated under vacuum
5. customthe precipitate formed
6. filtrationis filtered off