反应详情

To a solution of (2S)-3,3-dimethyl-butane-1,2-diol (3.1 g, 26.3 mmol) in dichloromethane (25 ml) is added pyridine (4.3 ml, 52.6 mmol). To the mixture is then added dropwise a solution of 4-toluenesulfonyl chloride (5.0 g, 26.3 mmol) in dichloromethane (25 ml) at 0° C. The reaction mixture is warmed to room temperature and stirred for additional 16 h. The reaction mixture is diluted with dichloromethane (50 ml) and washed with 10% copper(II) sulfate solution (2×30 ml). The organic layer is dried over sodium sulfate and evaporated to get the crude product, which is purified by column chromatography (silica gel, 5% ethyl acetate/hexane) affording 4-methyl-benzenesulfonic acid [(2S)-2-hydroxy-3,3-dimethyl-butyl]ester (4.2 g, 14.4 mmol, 54%).

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2. dry with materialThe organic layer is dried over sodium sulfate
3. customevaporated
4. customto get the crude product, which
5. customis purified by column chromatography (silica gel, 5% ethyl acetate/hexane)