Reacción #71352

Ecuación de reacción

hydride

5-nitro-pyridine-2-carboxylic acid ethyl ester

→

title compound

Rendimiento 49.8%

5-Nitro-pyridine-2-carbaldehyde

Rendimiento 49.8%

Disolventes

DCM

Condiciones de reacción

Tratamiento posterior

1. 1
   Otroquenched by addition of an aqueous solution of potassium sodium tartrate
2. 2
   workup.ADDITIONdiluted with DCM and H2O
3. 3
   Filtraciónfiltered through a pad of celite
4. 4
   ExtracciónThe filtrate was extracted several times with DCM
5. 5
   LavadoThe organic phase was washed with H2O and brine
6. 6
   Secadodried (Na2SO4)
7. 7
   Filtraciónfiltered
8. 8
   Concentraciónconcentrated
9. 9
   OtroThe residue was purified by by silica gel column chromatography (EtOAc/Hex, 1:1)

Procedimiento

Diisobutylaluminiumo hydride (1 M in DCM, 44 mL, 44 mmol, 1.3 equiv) was added dropwise to a cold (−78° C.) solution of 5-nitro-pyridine-2-carboxylic acid ethyl ester (step 39.4) (6.56 g, 33.5 mmol) in DCM (130 mL), under an argon atmosphere. The reaction mixture was allowed to warm to 5° C., quenched by addition of an aqueous solution of potassium sodium tartrate, diluted with DCM and H2O, stirred for 16 h at rt, and filtered through a pad of celite. The filtrate was extracted several times with DCM. The organic phase was washed with H2O and brine, dried (Na2SO4), filtered and concentrated. The residue was purified by by silica gel column chromatography (EtOAc/Hex, 1:1) to provide 2.54 g of the title compound as a beige solid: ESI-MS: 151.1 [M−H]−.

Fuente