反应详情

温度

-78 °C

A solution of (S)-4-formyl-2,3-dihydro-pyrrole-1,2-dicarboxylic acid 1-tert-butyl ester 2-ethyl ester (3.32 g, 12.3 mmol) in CH2Cl2 (51.4 mL) was cooled at −78° C. under nitrogen atmosphere, solid NaBH4 (1 g, 24.7 mmol) was added portionwise maintaining the temperature at −78° C. MeOH (25.7 mL) was added dropwise and the reaction mixture was allowed to reach 0° C. and was stirred 1 h30 at 0° C. The reaction was quenched with an aqueous saturated solution of NH4Cl and extracted with CH2Cl2 (×3). The combined organic layers were washed with brine, dried (Na2SO4), filtered and concentrated. The crude residue was purified by flash column chromatography on silica gel (c-hexane to c-hexane/EtOAc 1:1 to EtOAc) to give the desired material as a yellow oil. Rf, TLC (c-hexane/EtOAc 1:1)=0.30; MS (UPLC-MS): 272.2 [M+H]+, 316 [M+HCOO]−; tR (HPLC conditions f): 1.74 min.

1. customto reach 0° C.
2. customThe reaction was quenched with an aqueous saturated solution of NH4Cl
3. extractionextracted with CH2Cl2 (×3)
4. washThe combined organic layers were washed with brine
5. dry with materialdried (Na2SO4)
6. filtrationfiltered
7. concentrationconcentrated
8. customThe crude residue was purified by flash column chromatography on silica gel (c-hexane to c-hexane/EtOAc 1:1 to EtOAc)