反应详情

A solution of 0.4 g of the compound obtained in EXAMPLE 3 in 5 ml of pyridine is cooled to 0° C. and 0.1 g of methanesulfonyl chloride is added. The mixture is stirred for 18 hours, the temperature being allowed to rise to RT, and evaporated under vacuum. The residue is extracted with AcOEt, washed with a 5% solution of potassium hydrogensulfate, dried over sodium sulfate and evaporated under vacuum. The residue due is chromatographed on silica using a DCM/AcOEt mixture (98/2; v/v) as the eluent to give the expected product after crystallization from a DCM/iso ether mixture. m=0.22 g. M.p.=252° C.

1. customto rise to RT
2. customevaporated under vacuum
3. extractionThe residue is extracted with AcOEt
4. washwashed with a 5% solution of potassium hydrogensulfate
5. dry with materialdried over sodium sulfate
6. customevaporated under vacuum
7. customThe residue due is chromatographed on silica using a DCM/AcOEt mixture (98/2; v/v) as the eluent