1,4-Dibromobutane → HCID 19097482, compound

A solution of 1,2,3,4-tetramethyl-3-piperidineethanamine (9.8 g, 53 mmol) in acetonitrile (50 mL) was added dropwise over about 2 hours to a suspension of 1,4-dibromobutane (6.6 mL, 55.7 mmol) and potassium carbonate (26 g, 200 mmol) in acetonitrile (250 mL). The reaction mixture was stirred at room temperature for 24 hours, diluted with ether and the inorganic salts were removed by filtration. The solvent was removed in vacuo and the oily residue was purified by column chromatography on silica gel eluting with 2% isopropylamine/hexanes to afford 5.8 g (46%) of 1,2,3,4-tetramethyl-3-[2-(1-pyrrolidinyl)ethyl]piperidine. The product was dissolved in ether (25 mL) and treated with 6.5N ethereal HCl (10 mL) at 0° C. The mixture was warmed to room temperature, diluted with ether (10 mL) and cooled back to 0° C. to precipitate the dihydrochloride salt. The salt (4.3 g) was isolated as a white solid and had a melting point of 225°-227° C. (dec.) when recrystallized from ether (35 mL).

1. customthe inorganic salts were removed by filtration
2. customThe solvent was removed in vacuo
3. customthe oily residue was purified by column chromatography on silica gel eluting with 2% isopropylamine/hexanes

ORD record

ord-8560bcc32697493b9b7f500cff0cd80c

Source dataset

uspto-grants-1994_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05290796