反应详情

温度

-70 °C

A solution of the title B compound, 5-[5-(2,4-dimethoxy-benzyl)-1,1,4-trioxo-1,2,5-thiadiazolidin-2-ylmethyl]-thiophene-2-carbaldehyde (545 mg, 1.33 mmol) in dry THF (8 mL) is added dropwise to a cold (−70° C.) solution of isopentylmagnesium bromide (2.22 mmol) in dry THF (10 mL) keeping the temperature below −65° C. The mixture is stirred at −70° C. for 45 min and the reaction is quenched with saturated aqueous NH4Cl solution. The mixture is diluted with EtOAc and the layers are separated. The organic layer is dried over anhydrous MgSO4 and the solvent is evaporated. The residue is chromatographed on silica gel using 0→100% EtOAc in hexane as the eluent to afford 2-(2,4-dimethoxy-benzyl)-5-(5-(1-hydroxy-4-methyl-pentyl)-thiophen-2-ylmethyl]-1,1-dioxo-1,2,5-thiadiazolidin-3-one a yellow oil: [M+NH4]+=500.

1. customthe temperature below −65° C
2. customthe reaction is quenched with saturated aqueous NH4Cl solution
3. additionThe mixture is diluted with EtOAc
4. customthe layers are separated
5. dry with materialThe organic layer is dried over anhydrous MgSO4
6. customthe solvent is evaporated
7. customThe residue is chromatographed on silica gel using 0→100% EtOAc in hexane as the eluent