反应详情

A mixture of 274 mg (0.747 mmol) of 3-(4-benzyloxy-phenyl)-2-cyclohexyl-3-oxo-propionic acid methyl ester, 106 mg (0.747 mmol) of 5-amino-1H-pyrazole-3-carboxylic acid methyl ester, 15 mg (10 mol %) of p-toluenesulfonic acid monohydrate (PTSA), and 10 mL of toluene was heated at reflux for 88 h. The reaction mixture was then concentrated to a residue which was chromatographed on silica gel (Biotage; gradient elution 2% to 20% ethyl acetate in dichloromethane) to afford 55 mg (16% yield) of desired 5-(4-benzyloxy-phenyl)-6-cyclohexyl-7-oxo-4,7-dihydro-pyrazolo[1,5-a]pyrimidine-2-carboxylic acid methyl ester as a solid as indicated by 1H NMR; LC-MS—calcd for C27H27N3O4 [M++H]+: 458.2, found: 458.2.

1. temperaturewas heated
2. temperatureat reflux for 88 h
3. concentrationThe reaction mixture was then concentrated to a residue which
4. customwas chromatographed on silica gel (Biotage; gradient elution 2% to 20% ethyl acetate in dichloromethane)