1-Bromo-3-chloropropane → N-(3-chloropropyl)piperidine hydrochloride

To a solution of piperidine (0.45 g, 5.3 mmol) and 1-bromo-3-chloropropane (5.2 g, 33 mmol) in toluene (17.5 mL) was added tetra-n-butylammonium hydrogensulfate (0.51 g, 1.5 mmol) and a 25% aqueous sodium hydroxide (10 mL), and the resulting mixture was stirred at 40° C. for 3 hours. The reaction solution was cooled to room temperature, and the toluene layer was separated and was then washed with a saturated aqueous sodium chloride and was dried over anhydrous sodium sulfate. After sodium sulfate was filtered off, hydrochloric acid/methanol (2 mL) was added to the filtrate and themixture was concentrated. The resulting crude crystals were recrystallized from methanol/ether to afford the title compound (0.96 g, yield: 91%) as white crystals.

1. customthe toluene layer was separated
2. washwas then washed with a saturated aqueous sodium chloride
3. dry with materialwas dried over anhydrous sodium sulfate
4. filtrationAfter sodium sulfate was filtered off
5. additionhydrochloric acid/methanol (2 mL) was added to the filtrate and themixture
6. concentrationwas concentrated
7. customThe resulting crude crystals were recrystallized from methanol/ether

ORD record

ord-57df19c73770466f94050ddc8ddf1875

Source dataset

uspto-grants-2003_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06642228B1