4-chloro-7-fluoro-2,3-dihydroinden-1-one

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

Procedure: To a solution of 4-chloro-7-fluoro-2,3-dihydro-1H-inden-1-one (CAS No. 1260018-63-0, 900 mg, 4.88 mmol) in MeOH (30 mL) was added sodium borohydride (221 mg, 5.85 mmol) at room temperature. The reaction mixture was stirred for 20 minutes at room temperature. To the reaction was added 2N HCl, AcOEt and water at 0° C. The layers were separated. The organic layer was washed with brine and dried over MgSO4, then the solvent was evaporated in vacuo. To a solution of the residue in toluene (50 ml) was added p-toluenesulfonic acid monohydrate (100 mg, 0.53 mmol) and the reaction mixture was refluxed for 20 minutes. After cooling to room temperature, the reaction mixture was passed through NH silicagel and evaporated in vacuo. To a solution of the residue in THF (30 ml) and water (10 ml) was added NBS (842 mg, 4.73 mmol) and the reaction mixture was stirred for 20 hours at room temperature. AcOEt and brine were added to the mixture, and the layers were separated. The organic layer was successively washed with saturated aqueous Na2S2O3 and brine and then dried over MgSO4. The solvent was evaporated in vacuo. The residue was purified by silicagel flash column chromatography (Yamazen HI-FLASH™ column L size, 40 mL/min, gradient 0% to 40% AcOEt in n-heptane) to afford the title compound (675 mg, 2.54 mmol). The layers were separated The organic layer was washed with brine dried over MgSO4 the solvent was evaporated in vacuo the reaction mixture was refluxed for 20 minutes After cooling to room temperature evaporated in vacuo the reaction mixture was stirred for 20 hours at room temperature the layers were separated The organic layer was successively washed with saturated aqueous Na2S2O3 and brine dried over MgSO4 The solvent was evaporated in vacuo The residue was purified by silicagel flash column chromatography (Yamazen HI-FLASH™ column L size, 40 mL/min, gradient 0% to 40% AcOEt in n-heptane)