6-fluoro-3H-2-benzofuran-1-one

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 6-fluoroisobenzofuran-1(3H)-one (0.549 g, 3.61 mmol) in methanol (12 mL) and water (3 mL) at room temperature was added potassium hydroxide (0.350 g, 6.24 mmol). The mixture was heated at reflux for 1.5 hr. The mixture was concentrated under vacuum to a volume of about 3 mL. The residue was acidified with 1 M KHSO4 solution to pH 3-4. The insoluble material (inorganic salt) was removed by suction filtration and the filtrate was extracted with ethyl acetate (5×30 mL). The combined extract was dried over anhydrous MgSO4. Removal of solvent under vacuum provided the desired product (0.479 g, 2.82 mmol, 78% yield) as a white solid. The mixture was heated at reflux for 1.5 hr The mixture was concentrated under vacuum to a volume of about 3 mL The insoluble material (inorganic salt) was removed by suction filtration the filtrate was extracted with ethyl acetate (5×30 mL) The combined extract was dried over anhydrous MgSO4 Removal of solvent under vacuum

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of methyl 2-(bromomethyl)-5-fluorobenzoate (0.750 g, 3.04 mmol) and calcium carbonate (1.823 g, 18.21 mmol) in 1,4-dioxane (30 mL) and water (30.0 mL) was heated at reflux for 2.5 hr. The insoluble material was removed by filtration. The filtrate was concentrated under vacuum and then extracted with CH2Cl2 (4×30 mL). The combined extract was dried over anhydrous MgSO4. Removal of solvent under vacuum provided the desired product (0.423 g, 2.78 mmol, 92% yield) as a white solid. was heated at reflux for 2.5 hr The insoluble material was removed by filtration The filtrate was concentrated under vacuum extracted with CH2Cl2 (4×30 mL) The combined extract was dried over anhydrous MgSO4 Removal of solvent under vacuum

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: According to a similar procedure to that described in Example 4-(5), 6-fluoro-1(3H)-isobenzofuranone (described in Tetrahedron, 44, 4591 (1988); 1.52 g, 10 mmol) was reacted with an aqueous solution of sodium hydroxide (1.008N; 10 ml, 10 mmol), 4-methoxybenzyl chloride (1.57 g, 10 mmol), tetrazole (1.40 g, 20 mmol), bis(allyloxy)(diisopropylamino)phosphine (described in Tetrahedron Lett., 30, 4219 (1989); 3.0 g, 12.2 mmol), and tert-butyl hydroperoxide (80% di-tert-butyl peroxide solution); Merck; 2.7 g, 24 mmol), and the reaction mixture was worked up to afford, after extraction, an oily residue. The residue was subjected to chromatography on a silica gel (90 g) column (ethyl acetate:hexane=1:4˜1:2) to give an oily mixture. The mixture was further subjected to chromatography on a silica gel (50 g) column (eluent; ethyl acetate:hexane=1:4˜1:2) to afford the title compound (1.22 g, 27% yield) as a colorless oil. to afford after extraction to give an oily mixture