C([O:3][C:4]([CH2:6][CH:7]1[CH2:16][C:15]2[C:10](=[CH:11][CH:12]=[C:13]([F:17])[CH:14]=2)[O:9][C:8]1([CH3:19])[CH3:18])=O)C.[H-].[Al+3].[Li+].[H-].[H-].[H-].O.[OH-].[Na+]>C(OCC)C>[CH3:18][C:8]1([CH3:19])[CH:7]([CH2:6][CH2:4][OH:3])[CH2:16][C:15]2[C:10](=[CH:11][CH:12]=[C:13]([F:17])[CH:14]=2)[O:9]1A solution of 3.4 g (12.7 mmol) of 3-ethoxycarbonylmethyl-2,2-dimethyl-6-fluoro-chroman in 40 ml of absolute diethyl ether is added dropwise within a period of 30 minutes, while cooling with ice, to a suspension of 0.97 g (25.5 mmol) of lithium aluminium hydride in 30 ml of absolute diethyl ether. The reaction mixture is then stirred for 2 hours at room temperature and then carefully decomposed with 1 ml of water, 1 ml of sodium hydroxide solution (15%) and 3 ml of water. The resulting precipitate is filtered off with suction and the filtrate is dried over sodium sulfate and concentrated by evaporation in vacuo, yielding 2.75 g (96% of the theoretical yield) of 2,2-dimethyl-6-fluoro-3-(2-hydroxyethyl)-chroman in the form of a light-yellow oil.
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