反应详情

A mixture of 12.71 g of the compound obtained in step B) and 8.9 g of 1,1'-carbonyldiimidazole in 130 ml of acetonitrile is refluxed for 3 hours. The solvent is evaporated off under vacuum, the residue is taken up with water, extracted with DCM, washed with a saturated solution of NaHCO3 and with water and dried over Na2SO4 and the solvent is evaporated off under vacuum. The residue is chromatographed on silica using a DCM/MeOH mixture (92/8; v/v) as the eluent. 8.9 g of the expected product are obtained after recrystallization from absolute ethanol. M.p.=204°-206° C.

1. temperatureis refluxed for 3 hours
2. customThe solvent is evaporated off under vacuum
3. extractionextracted with DCM
4. washwashed with a saturated solution of NaHCO3 and with water
5. dry with materialdried over Na2SO4
6. customthe solvent is evaporated off under vacuum
7. customThe residue is chromatographed on silica using a DCM/MeOH mixture (92/8; v/v) as the eluent