Fluorobenzene → HCID 10752867, compound

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Reaction Steps

To a solution of pyridine-3,4-dicarboxylic anhydride (56.04 g, 0.38 mol) in 950 mL of fluorobenzene is added AlCl3 (126.67 g, 0.95 mol) over 45 min. from a powder addition funnel. The mixture is heated to reflux for 12 hours, then allowed to cool and quenched with ice water. Addition of a concentrated NaOH solution results in a solid precipitate which is filtered. The basic aqueous fraction of the biphasic filtrate is separated, washed with Et2O (3×150 mL), and acidified to pH 2.5 with concentrated HCl to generate a white solid which is collected by vacuum filtration. The solid is washed with several portions of hot MeOH to generate pure 3-(4-fluorobenzoyl)pyridine-4-carboxylic acid. M.P. 308.5° C. The combined methanolic filtrates are evaporated and recrystallized from MeOH to generate 4-(4-fluorobenzoyl)-pyridine-3-carboxylic acid. M.P. 231°-232.5° C.

Provenance & Evidence