Iodine → [4,6-Bis(1,1-dimethylethyl)-5-hydroxy-2-pyrimidinyl](2-thienyl)methanone

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Reaction Steps

To a mixture of magnesium turnings (1.22 g, 50.7 mmol) in dry ethyl ether (16 mL) under nitrogen atmosphere is added a single crystal of iodine followed by freshly distilled 2-bromothiophene (2.50 mL, 30.0 mmol) dropwise over 1 hour. This mixture is refluxed 1 hour then cooled to room temperature. The molarity of the solution (1.06M) is determined by titration of a small sample with isopropanol. A portion of this 1.06M solution of thiophene magnesium bromide in ether (3.5 mL, 3.71 mmol) is added dropwise under nitrogen atmosphere to a solution of 4,6-bis(1,1-dimethylethyl)-5-hydroxy-N-methoxy-N-methyl-2-pyrimidinecarboxamide (0.50 g, 1.7 mmol) in tetrahydrofuran (15 mL) dropwise. The resulting mixture is stirred 16 hours, diluted with ethyl ether (15 mL), quenched with aqueous saturated ammonium chloride solution, and washed with water and brine solution. Concentration of the organic phase followed by purification by flash chromatography (SiO2, dichloromethane) and recrystallization from methanol and water gave 0.40 g (74 %) of title compound, mp 157.5°-159° C.

Provenance & Evidence