4-Fluorobenzoic anhydride

456-22-4

25569-77-1

GENERAL METHOD: p-Fluorobenzoic acid (1 mmol) was dissolved in anhydrous CH3CN (5 mL) with K2CO3 (1.5 mmol, 0.20 g), followed by the addition of TsCl (0.5 mmol, 0.10 g). The reaction mixture was stirred at room temperature for appropriate time (20-180 min, see Table 2) until TLC detection showed complete consumption of TsCl. After completion of the reaction, CH2Cl2 or Et2O (2 × 10 mL) was added to the mixture, stirred thoroughly and filtered. The organic layer was dried with CaCl2 and the solvent was subsequently evaporated to give high purity 4-fluorobenzoic anhydride.