2-Chlorothiazole → 1-(2-Chlorothiazol-5-yl)ethanone

関与物質

反応条件

反応手順

A solution of 2-chlorothiazole (2.5 g, 21 mmol) in THF (10 mL) was added dropwise to a chilled (−75° C.) 2.5 M hexanes solution of n-BuLi (9.2 mL, 23 mmol) in THF (70 mL). After the addition was complete the reaction mixture was stirred for 1 hr. Then a solution of N-methoxy-N-methylacetamide (2.4 g, 23 mmol) in THF (5 mL) was added. The reaction was allowed to stir overnight while warming to 25° C. The reaction was diluted with H2O and thrice extracted with ethyl ether. The organic portions were combined, washed with brine and then dried (Na2SO4). Filtration and removal of solvent gave a residue that was purified by flash chromatography on silica eluting with 5 percent Et2O in pentane, affording product as a white solid, 2.5 g, 15.5 mmol, 73 percent yield.

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