Perfluoro-1-butanesulfonyl fluoride → 4-[5-(Nonafluorobutane-1-sulfonyloxy)-2-(3,3,5,5-tetramethylcyclohexyl)phenyl]piperazine-1-carboxylic acid t-butyl ester

Beteiligte Stoffe

Reaktionsschritte

A mixture of 4-[5-hydroxy-2-(3,3,5,5-tetramethylcyclohexyl)phenyl]piperazine-1-carboxylic acid t-butyl ester (1.5 g, 3.60 mmol) produced in Example (81b), 4-dimethylaminopyridine (22.2 mg, 0.18 mmol), diisopropylethylamine (0.758 mL, 4.32 mmol) and dichloromethane (10 mL) was cooled in an ice water bath and stirred under a nitrogen atmosphere. Perfluorobutanesulfonyl fluoride (0.773 mL, 3.96 mmol) was then added dropwise thereto. After stirring for 1 hour and 20 minutes under the same conditions, stirring was continued for 16 hours at room temperature. Water was added to the reaction mixture and extraction was performed with dichloromethane. The separated organic layer was washed with brine and then dried over anhydrous magnesium sulfate. The desiccant was filtered off and the filtrate was concentrated under reduced pressure. The resultant residue was purified by NH silica gel column chromatography (ethyl acetate/heptane) to give 2.41 g of the title compound as a light yellow oil.

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