Bromide ion → 1-[2-(3-Nitro-pyrazol-1-ylmethyl)-oxazol-4-yl]-ethanone

Beteiligte Stoffe

Reaktionsschritte

In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), a solution of methanesulfonic acid 4-acetyl-oxazol-2-ylmethyl ester (70 mg, 0.32 mmol) in acetone (5.0 mL) was treated with K2CO3 (223 mg, 1.60 mmol) followed by 5-nitro-1H-pyrazole (37 mg, 0.32 mmol) and TBA bromide (21 mg, 0.06 mmol). The reaction mixture was stirred at rt until completion. The solvent was removed under reduced pressure and water (10 mL) followed by EA (10 mL) were added. The aq. layer was extracted with EA (10 mL) and the combined org. extracts were dried over Na2SO4, filtered, and the solvents were removed under reduced pressure. Purification of the residue by FC (1:1 hept-EA) gave the title compound as a yellow solid. TLC: rf (EA)=0.50. LC-MS-conditions 02: tR=0.74 min; [M+H]+=237.31.

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