反应详情

Carbonyl diimidazole (421 mg, 2.60 mmol) was added to a solution of 4-isobutyl benzoic acid (386 mg, 2.17 mmol) and DMF (10 mL) and stirred for 2 hours at room temperature. N′-hydroxy-3-(hydroxymethyl)benzenecarboximidamide (360 mg, 2.17 mmol) was added to the reaction mixture and stirred for 18 hours at ambient temperature. The reaction was diluted with water and extracted with ethyl acetate (2×) and the combined organic extracts were washed with 0.25 N sodium hydroxide, water and brine. The organic layer was dried (MgSO4), filtered and concentrated in vacuo to give a crude residue. The crude residue was dissolved in THF (6 mL) and treated with tetrabutyl ammonium fluoride (1M in THF, 2.4 mL, 2.38 mmol). The solution was stirred at ambient temperature for 18 hours, diluted with brine and extracted with ethyl acetate. The combined organic layers were concentrated in vacuo. Purification by flash chromatography (silica, 1:9 to 2:3 EtOAc:hexanes) provided the title compound (193 mg, 29% yield) as a solid.

1. stirringstirred for 18 hours at ambient temperature
2. extractionextracted with ethyl acetate (2×)
3. washthe combined organic extracts were washed with 0.25 N sodium hydroxide, water and brine
4. dry with materialThe organic layer was dried (MgSO4)
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customto give a crude residue
8. stirringThe solution was stirred at ambient temperature for 18 hours
9. extractionextracted with ethyl acetate
10. concentrationThe combined organic layers were concentrated in vacuo
11. customPurification by flash chromatography (silica, 1:9 to 2:3 EtOAc:hexanes)