Dichloromethane → 8-ethyl-4-methyl-2-(methylthio)-6-(1H-pyrazol-5-yl)pyrido[2,3-d]pyrimidin-7(8H)-one

Participants

Reaction Steps

To a solution of 6-bromo-8-ethyl-4-methyl-2-(methylthio)pyrido[2,3-d]pyrimidin-7(8H)-one (0.765 g, 2.43 mmol) in DME-H2O (10:1 11 mL) was added 1H-pyrazol-5-ylboronic acid (Frontier, 0.408 g, 3.65 mmol), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) complex with CH2Cl2 (Pd(dpppf), 0.198 g, 0.243 mmol) and triethylamine (0.736 g, 7.29 mmol) at room temperature. Then the reaction mixture was heated to reflux and reacted for 4 h. After cooling down to room temperature, the reaction mixture was partitioned with water and ethyl acetate. After separation, the organic layer was dried with Na2SO4, and the product 8-ethyl-4-methyl-2-(methylthio)-6-(1H-pyrazol-5-yl)pyrido[2,3-d]pyrimidin-7(8H)-one (0.567 g, 77% yield) was obtained by silica gel column chromatography. 1H NMR (400 MHz, CDCl3): δ 13.3 (bs, 1H), 8.54 (s, 1H), 7.82-7.07 (m, 2H), 4.45 (q, J=7.2 Hz, 2H), 2.71 (s, 3H), 2.60 (s, 3H), 1.26 (t, J=7.2 Hz, 3H).

Provenance & Evidence