反应详情

温度

180 °C

A mixture of 1-cyclopentyl-3-methyl-5-amino-1H-pyrazole-4-carboxamide (3.98 g, 0.019 mol), 2-propoxybenzaldehyde (6.35 g, 0.038 mol), xylenes (150 ml) and methanesulfonic acid (0.5 ml) was heated at reflux for 39 hours with azeotropic removal of water. The reaction mixture was concentrated in vacuo and the residue was treated with 10% K2CO3 and ether. The layers were separated, the aqueous layer was extracted with ether and the combined ether layers were concentrated in vacuo. Analysis of the reaction mixture by TLC indicated that the reaction was not yet complete, therefore, the mixture was heated at 180° C. on an oil bath. The residue was dissolved in chloroform, and purified by column chromatography on silica gel eluting with hexane (100%) followed by ether (100%) to afford 2.67 g (41%) of 1-cyclopentyl-3-methyl-6-(2-propoxyphenyl)-pyrazolo[3,4-d]pyrimidin-4-one, m.p. 130°-132° C.

1. temperaturewas heated
2. concentrationThe reaction mixture was concentrated in vacuo
3. additionthe residue was treated with 10% K2CO3 and ether
4. customThe layers were separated
5. extractionthe aqueous layer was extracted with ether
6. concentrationthe combined ether layers were concentrated in vacuo
7. dissolutionThe residue was dissolved in chloroform
8. custompurified by column chromatography on silica gel eluting with hexane (100%)