Sodium Carbonate → 5-amino-1-[4-(2-ethyl-5,7-dimethyl-pyrazolo[1,5-a]pyrimidin-3-ylmethyl)-phenyl]-3-methyl-1H-pyrazole-4-carboxylic acid ethyl ester

Participants

Reaction Conditions

Reaction Steps

[4-(2-Ethyl-5,7-dimethyl-pyrazolo[1,5-a]pyrimidin-3-ylmethyl)-phenyl]-hydrazine (15) (1.8 g, 6.1 mmol) was dissolved in 40 ml water/AcOH (1:3), and after addition of (E)-ethyl 2-cyano-3-ethoxyacrylate (1.24 g, 7.3 mmol) and sodium acetate (1.1 g, 13.4 mmol) the reaction mixture was stirred for 3 h at 100° C. Sodium carbonate was added (pH 11). The organic layer was extracted 2 times with EtOAc, washed with water and brine, dried over Na2 SO4 and concentrated. The crude product was purified by chromatography (50-90% EtOAc in cyclohexane).

Provenance & Evidence