Diethyl (cyanomethyl)phosphonate → 3-[3-(5-Ethyl-2,6-dimethoxy-pyrimidine-4-carbonyl)-5-methyl-phenyl]-acrylonitrile

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Reaction Steps

To a stirred mixture of 3-(5-ethyl-2,6-dimethoxy-pyrimidine-4-carbonyl)-5-methyl-benzaldehyde (3.11 g, 9.9 mmol) and diethyl cyanomethyl-phosphonate (1.6 ml, 10 mmol) in anhydrous THF (20 ml) at 0° C. (ice bath) under nitrogen atmosphere, was added potassium t-butoxide (1.26 g, 11.2 mmol). After 1 hr., the mixture was stirred at room temperature for 5 hr. The mixture was then partitioned between ether and water. The ether layer was taken, dried with anhydrous magnesium sulfate, filtered, and evaporated in vacuo to give a pale yellow syrup. The crude product was purified by silica gel column chromatography (eluent, EA:hexanes (1:4)) to afford 2.39 g (72%) of a white solid. m.p. 165-166° C.; 1H NMR (200 MHz, CDCl3) δ 1.09 (3H, t, J=7.8 Hz), 2.42-2.53 (5H, m), 3.96 (3H, s), 4.09 (3H, s), 5.93 (1H, d, J=16.8 Hz), 7.40 (1H, s, J=16.8 Hz), 7.50 (1H, s), 7.73 (1H, s), 7.79 (1H, s).

Provenance & Evidence