Reacción #157118

Ecuación de reacción

N2

ethyl 2,6-dichloro-5-nitropyrimidine-4-carboxylate

magnesium oxide

→

ethyl 5-amino-2-chloropyrimidine-4-carboxylate

Disolventes

1,4-dioxane

Condiciones de reacción

Tratamiento posterior

1. 1
   Otroflushed
2. 2
   OtroThe reaction was purged with H2 under atmospheric pressure at rt
3. 3
   Otroto purge with H2 under atmospheric pressure for 6 h at rt
4. 4
   FiltraciónThe crude solids were filtered through a pad of Celite on a paper
5. 5
   Lavadowashed with CH2Cl2
6. 6
   OtroThe filtrate was transferred to a separatory funnel
7. 7
   Lavadowashed twice with H2O and once with brine
8. 8
   Secadodried over anhydrous Na2SO4
9. 9
   Filtraciónfiltered
10. 10
    Concentraciónconcentrated in vacuo
11. 11
    workup.DISSOLUTIONThe crude product was dissolved in CH2Cl2
12. 12
    Otropurified by flash chromatography (10-20-30% EtOAc in hexanes)

Procedimiento

10% Palladium on carbon (0.2 eq) was added to a N2-flushed mixture of ethyl 2,6-dichloro-5-nitropyrimidine-4-carboxylate (1 eq) and magnesium oxide (2 eq) in 1,4-dioxane (0.15 M). The reaction was purged with H2 under atmospheric pressure at rt. After 16 h additional portions of 10% Pd/C (0.3 eq) and MgO (5 eq) were added and the reaction continued to purge with H2 under atmospheric pressure for 6 h at rt. The crude solids were filtered through a pad of Celite on a paper lined Buchner funnel and washed with CH2Cl2. The filtrate was transferred to a separatory funnel, washed twice with H2O and once with brine, then dried over anhydrous Na2SO4, filtered, and concentrated in vacuo. The crude product was dissolved in CH2Cl2, loaded onto a SiO2 column, and purified by flash chromatography (10-20-30% EtOAc in hexanes) to give ethyl 5-amino-2-chloropyrimidine-4-carboxylate. LC/MS (m/z): 202.0 (MH+).

Fuente