Formaldehyde → 4-Fluoro-2-hydroxybenzaldehyde

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Into a 20-L 4-necked round-bottom flask purged and maintained with an inert atmosphere of nitrogen was placed a solution of 3-fluorophenol (400 g, 3.57 mol, 1.00 equiv) in CH3CN (5 L), followed by the addition of MgCl2 (1018 g, 3.00 equiv) in several batches at 0° C. To this was added TEA (1443 g, 14.26 mol, 4.00 equiv) dropwise with stirring at 0-5° C., followed by paraformaldehyde (640 g, 6.00 equiv). The resulting solution was stirred at 80° C. for 3 h, cooled to 20° C., quenched by the addition of 5 L of 2N HCl and extracted with 3×3 L of ethyl acetate. The organic layers were combined, dried over anhydrous sodium sulfate and concentrated under vacuum to afford 545 g (crude) of 4-fluoro-2-hydroxybenzaldehyde as a yellow solid.

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