Reaction SMILES: [Br:1][C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=O)=[C:4]([CH2:11][O:12][C:13]2[CH:18]=[CH:17][C:16]([F:19])=[CH:15][CH:14]=2)[CH:3]=1.FC(F)(F)C(OC(=O)C(F)(F)F)=O.[OH-].[Na+]>ClCCl>[Br:1][C:2]1[CH:10]=[CH:9][C:5]2[C:6](=[O:8])[C:14]3[CH:15]=[C:16]([F:19])[CH:17]=[CH:18][C:13]=3[O:12][CH2:11][C:4]=2[CH:3]=1
Reactant: O=C(O)c1ccc(Br)cc1COc1ccc(F)cc1
Agent: [Na+]
Agent: [OH-]
Solvent: ClCCl
Solvent: O=C(OC(=O)C(F)(F)F)C(F)(F)F
Product: O=C1c2ccc(Br)cc2COc2ccc(F)cc21
Temperature: 25 °C
Reaction time: 6 h
Yield: 34.4 %

Procedure:
[step 1] 5-Bromophthalide (6.00 g, 28.2 mmol) was dissolved in DMF (10 mL), 4-fluorophenol (3.15 g, 28.2 Jinni) was added, and the mixture was heated to 120° C. 28% Sodium methoxide methanol solution (5.5 mL, 28.2 mmol) was added and the mixture was stirred with heating for 4 hr. 2 mol/L Hydrochloric acid was added dropwise to the reaction mixture to neutralize the reaction mixture, and the mixture was extracted 3 times with chloroform. The combined organic layer was dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (chloroform/methanol=9/1) to give 4-bromo-2-(4-fluorophenoxy)methylbenzoic acid (3.37 g, 36%). [step 2] 4-Bromo-2-(4-fluorophenoxy)methylbenzoic acid (3.37 g, 10.4 mmol) obtained in step 1 was dissolved in dichloromethane (35 mL), trifluoroacetic anhydride (2.2 mL) and boron trifluoride diethyl ether complex (0.091 mL, 0.726 mmol) were added, and the mixture was stirred at room temperature for 6 hr. 2 mol/L Aqueous sodium hydroxide solution was added to the reaction mixture, and the mixture was extracted 3 times with dichloromethane. The combined organic layer was dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The obtained residue was crystallized from ethanol and collected by filtration to give 8-bromo-2-fluoro-6,11-dihydrodibenzo[b,e]oxepin-11-one (1.10 g, 34%). [step 3] Using 8-bromo-2-fluoro-6,11-dihydrodibenzo[b,e]oxepin-11-one (1.10 g, 3.58 mmol) obtained in step 2 instead of 2-chloro-5,11-dihydrobenzooxepino[3,4-b]pyridin-5-one, and in the same manner as in Reference Example B10, step 2, (E)-2-[8-bromo-2-fluoro-6,11-dihydrodibenzo[b,e]oxepin-11-ylidene]propiononitrile and (Z)-2-[8-bromo-2-fluoro-6,11-dihydrodibenzo[b,e]oxepin-11-ylidene]propiononitrile (0.980 g, 79%) was obtained. [step 4] Using (E)-2-[8-bromo-2-fluoro-6,11-dihydrodibenzo[b,e]oxepin-11-ylidene]propiononitrile and (Z)-2-[8-bromo-2-fluoro-6,11-dihydrodibenzo[b,e]oxepin-11-ylidene]propiononitrile (0.980 g, 2.85 mmol) obtained in step 3 instead of (E)-2-(8-bromo-6,11-dihydrodibenzo[b,e]oxepin-11-ylidene)cyclopropylacetonitrile and (Z)-2-(8-bromo-6,11-dihydrodibenzo[b,e]oxepin-11-ylidene)cyclopropylacetonitrile, and in the same manner as in Reference Example B9, step 2, propyl(E)-11-(1-cyanoethylidene)-2-fluoro-6,11-dihydrodibenzo[b,e]oxepine-8-carboxylate (0.210 g, 21%) was obtained. [step 5] Using propyl(E)-11-(1-cyanoethylidene)-2-fluoro-6,11-dihydrodibenzo[b,e]oxepine-8-carboxylate (0.210 g, 0.598 mmol) obtained in step 4 instead of propyl(E)-11-cyanocyclopropylmethylene-6,11-dihydrodibenzo[b,e]oxepine-8-carboxylate and propyl(Z)-11-cyanocyclopropylmethylene-6,11-dihydrodibenzo[b,e]oxepine-8-carboxylate, and in the same manner as in Reference Example B9, step 3, (E)-2-(2-fluoro-8-hydroxymethyl-6,11-dihydrodibenzo[b,e]oxepin-11-ylidene)propiononitrile (0.230 g, 100%) was obtained.