反应详情

A solution of di-butyl azodicarboxylate (145 mg, 0.6275 mmol) in 2 mL of dry THF is added dropwise to a suspension of 3H-Imidazole-4-carboxylic acid methyl ester (79 mg, 0.6275 mmol), PPh3 (165 mg, 0.6275 mmol), and 4-Hydroxy-3,3-dimethyl-3,4-dihydro-1H-quinolin-2-one (80 mg, 0.418 mg) in 3 mL of dry THF at 0° C. The resulting mixture is slowly warmed up to room temperature, and stirred for 2 h. The reaction is quenched with 2 M HCl and stirred for another 0.5 h. After concentration, the residue is dissolved in HCl (2 M) and extracted with ethyl acetate (20 mL×3). The aqueous layer is adjusted to pH 8-9 by addition of saturated NaHCO3 solution. Subsequently, the mixture is extracted with ethyl acetate (20 mL×3). The combined extracts are washed with brine, and dried over anhydrous Na2SO4. After concentration, the residue is purified by flash column first then by reverse phase HPLC and gives two title regioisomers.

1. customThe reaction is quenched with 2 M HCl
2. stirringstirred for another 0.5 h
3. concentrationAfter concentration
4. dissolutionthe residue is dissolved in HCl (2 M)
5. extractionextracted with ethyl acetate (20 mL×3)
6. additionThe aqueous layer is adjusted to pH 8-9 by addition of saturated NaHCO3 solution
7. extractionSubsequently, the mixture is extracted with ethyl acetate (20 mL×3)
8. washThe combined extracts are washed with brine
9. dry with materialdried over anhydrous Na2SO4
10. concentrationAfter concentration
11. customthe residue is purified by flash column first
12. customby reverse phase HPLC and gives two title regioisomers