反应详情

To a stirred solution of 5-(2,3-dichlorobenzenesulphonylamino)-6-methoxy-3-methylpyrazine-2-carboxylic aicd, methyl ester (Example 119) (0.19 g) in tetrahydrofuran (10 mL) under an atmosphere of nitrogen was added a solution of lithium triethylborohydride (1.7 mL of a 1M solution in tetrahydrofuran). The reaction mixture was stirred at room temperature for 1 h, before quenching with aqueous ammonium chloride and extraction into dichloromethane. The organic phase was dried (MgSO4), filtered and evaporated to give the crude product as a colourless oil. Chromatography on silica gel eluting with dichloromethane/ethyl acetate/acetic acid (150:50: 1) gave the title compound as a white solid (0.38 g).

1. custombefore quenching with aqueous ammonium chloride and extraction into dichloromethane
2. dry with materialThe organic phase was dried (MgSO4)
3. filtrationfiltered
4. customevaporated
5. customto give the crude product as a colourless oil