N-Methylbenzylamine → N-benzyl-3-chloro-N-methylpropan-1-amine

Temperature

40 °C

260 ml of 1-bromo-3-chloropropane were dissolved in 400 ml of acetone. 230 g of potassium carbonate were added to the solution. A solution of 115 ml of N-methyl-N-benzylamine in 115 ml of acetone was added dropwise to the reaction mixture with stirring at a bath temperature of 40° C., the addition being distributed over a period of 30 minutes. The reaction mixture was subsequently stirred at a temperature of 40° C. for 4 hours. The precipitated salts were then filtered out. The filtrate was concentrated under reduced pressure at a temperature of 40° C. The residue was acidified to a pH of 1 using 16% strength aqueous hydrochloric acid solution and was washed 3 times with tert-butyl methyl ether in order to remove unreacted 1-bromo-3-chloropropane. The aqueous phase was subsequently brought to a pH of 8 by addition of 16% strength sodium hydroxide solution and was extracted repeatedly with ethyl acetate. The combined ethyl acetate phases were dried with magnesium sulfate and concentrated. 71 g of 3-(N-benzyl-N-methylamino)-propyl chloride were obtained.

1. additionthe addition
2. stirringThe reaction mixture was subsequently stirred at a temperature of 40° C. for 4 hours
3. filtrationThe precipitated salts were then filtered out
4. concentrationThe filtrate was concentrated under reduced pressure at a temperature of 40° C
5. washwas washed 3 times with tert-butyl methyl ether in order
6. customto remove unreacted 1-bromo-3-chloropropane
7. additionThe aqueous phase was subsequently brought to a pH of 8 by addition of 16% strength sodium hydroxide solution
8. extractionwas extracted repeatedly with ethyl acetate
9. dry with materialThe combined ethyl acetate phases were dried with magnesium sulfate
10. concentrationconcentrated

ORD record

ord-c1511f16dc374407bdc991a015c4a7c1

Source dataset

uspto-grants-1997_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05679699