169457-73-2

General procedure for the synthesis of N-Boc-4-(2-bromoethyl)piperidine from N-Boc-4-piperidine ethanol: N-Boc-4-(2-hydroxyethyl)piperidine (0.95 g, 4.17 mmol) was dissolved in anhydrous tetrahydrofuran (20 mL), followed by carbon tetrabromide (1.34 g, 4.0 mmol). A solution of triphenylphosphine (1.15 g, 4.38 mmol) in anhydrous tetrahydrofuran (2 mL) was added slowly and dropwise over 2 hours. The reaction mixture was stirred at room temperature for 18 hours. After completion of the reaction, ether (50 mL) was added to the mixture, the reaction mixture was filtered and the filtrate was concentrated under reduced pressure. The resulting crude product was purified by silica gel column chromatography (eluent ratio 9:1 hexane:ethyl acetate) to afford the target product N-Boc-4-(2-bromoethyl)piperidine (1.05 g, 86% yield) as an oil.

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