反应详情

Sodium triacetoxyborohydride (1.4 g, 6.6 mmol, 2 equiv) was added portionwise to a cold (5° C.) solution of 5-nitro-pyridine-2-carbaldehyde (Step 39.3) (0.5 g, 3.3 mmol) and N-methyl-piperazine (0.4 mL, 3.6 mmol, 1.1 equiv) in DCM (10 mL). The reaction mixture was allowed to warm to rt, stirred for 16 h, diluted with DCM and saturated solution of NaHCO3, and extracted with DCM. The organic phase was washed with H2O and brine, dried (Na2SO4), filtered and concentrated. The residue was purified by silica gel column chromatography (DCM/MeOH/NH3aq, 91:8:1) to provide 0.532 g of the title compound as a yellow solid: ESI-MS: 237.2 [M+H]+; TLC: Rf=0.31 (DCM/MeOH/NH3aq, 91:8:1).

1. extractionextracted with DCM
2. washThe organic phase was washed with H2O and brine
3. dry with materialdried (Na2SO4)
4. filtrationfiltered
5. concentrationconcentrated
6. customThe residue was purified by silica gel column chromatography (DCM/MeOH/NH3aq, 91:8:1)