Methyl Ethyl Ketone → 1,2-diethyl-2-methyl-6-(pyridin-4-yl)-2,3-dihydrothieno[3,2-d]pyrimidin-4(1H)-one

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Reaction Conditions

Reaction Steps

A mixture of 3-(ethylamino)-5-(pyridin-4-yl)thiophene-2-carboxamide (0.100 g, 0.400 mmol), 2-butanone (2.5 mL), p-toluenesulfonic acid monohydrate (0.0095 g, 0.050 mmol) and acetic acid (2.0 mL) was stirred for 1 h at 120° C. in a sealed tube. Then, this mixture was stirred for 3 h at 150° C. in a sealed tube. The mixture was poured into sat. aqueous sodium hydrogen carbonate (150 mL). Extraction with ethyl acetate (100 mL), drying over magnesium sulfate, filtration and concentration at reduced pressure gave an oil. The oil was purified by column chromatography (Combiflash, 40 g silica gel, dichloromethane to ethyl acetate) to afford the title compound (0.0547 g, 45%) as a yellow solid:

Provenance & Evidence