[OH:1][C:2]1[C:3]([CH3:11])=[C:4]([CH:8]=[CH:9][CH:10]=1)[C:5]([OH:7])=[O:6].[H-].[Na+].[CH2:14](Br)[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1.O>O1CCCC1.CN(C)C=O>[CH2:14]([O:1][C:2]1[C:3]([CH3:11])=[C:4]([CH:8]=[CH:9][CH:10]=1)[C:5]([OH:7])=[O:6])[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1To a solution of 3-hydroxy-2-methyl-benzoic acid (55, 5.0 g, 0.033 mol) in tetrahydrofuran (100 mL) and N,N-dimethylformamide (50 mL), sodium hydride (4.4 g as 60% dispersion in mineral oil, 0.11 mol) was added slowly over 30 minutes and the reaction was stirred at 0° C. under an atmosphere of nitrogen. The reaction mixture was allowed to warm to room temperature, then stirred at room temperature for 1 hour. Benzyl bromide (9.0 mL, 0.076 mol) was added slowly into the reaction mixture, and the reaction mixture was stirred at room temperature overnight. The reaction mixture was poured into water, extracted with ethyl acetate, washed with a solution of ammonium chloride and ammonium hydroxide (4:1), brine, and dried over magnesium sulfate. After removal of solvent, the residue was purified by silica gel column chromatography eluting with ethyl acetate in hexane to provide the compound as a white solid (56, 5.8 g, 73%).
Wird geladen…