[CH:1]([C:4]1[CH:12]=[CH:11][C:7]([C:8](O)=[O:9])=[C:6]([O:13][CH2:14][O:15][CH3:16])[CH:5]=1)([CH3:3])[CH3:2].CN1CCOCC1.ClC(OCC)=O.[BH4-].[Na+].C(=O)=O>O1CCCC1.CO>[CH:1]([C:4]1[CH:12]=[CH:11][C:7]([CH2:8][OH:9])=[C:6]([O:13][CH2:14][O:15][CH3:16])[CH:5]=1)([CH3:3])[CH3:2]To a solution of 4-isopropyl-2-(methoxymethoxy)benzoic acid, which may be prepared as described in Exmple 6-B, (2.40 g, 11.0 mmol) and 4-methylmorpholine (1.18 mL, 11.0 mmol) in 50 mL dry tetrahydrofuran at −10° C. was added dropwise ethyl chloroformate (1.02 mL, 11.0 mmol). After stirring at −10° C. for 20 min, sodium borohydride (1.21 g, 33.0 mmol) was added all at once. Methanol (150 mL) was cautiously added dropwise. Once the vigorous evolution of carbon dioxide had significantly decreased, the remaining methanol was added. Stirring was continued for 30 min, and the reaction was quenched with 10% acetic acid in water. The volatile solvents were removed, and the remaining material was diluted with ether. The ether was extracted with saturated NaHCO3 (2×), water (2×), brine (1×), and dried over MgSO4. The crude material was purified by chromatography over silica, using an eluent gradient of 10-30% ethyl acetate in hexanes, to afford the alcohol (1.16 g, 50%).
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