Reaction #549682

Reaction equation

hydrogen bromide

sulphur trioxide

4-(3-methyl-2-pyridyl)butylamine dihydrobromide

→

4-(5-bromo-3-methyl-2-pyridyl)-butylamine

Yield 51.5%

Solvents

dichloromethane

1,1,2-trifluorotrichloroethane

1,1,2-trifluorotrichloroethane

Conditions

Workup

1. 1
   Otherprepared
2. 2
   Temperaturethe mixture was heated
3. 3
   Temperatureunder reflux for ca 16 hr
4. 4
   OtherThe solvent was removed by distillation
5. 5
   Otherwas removed by acetylation

Procedure

A solution of sulphur trioxide (150 ml) in 1,1,2-trifluorotrichloroethane (350 ml) was added over ca 30 min. to a suspension of 4-(3-methyl-2-pyridyl)butylamine dihydrobromide (17 g) [prepared by passing hydrogen bromide gas through a solution of the amine in dichloromethane] in 1,1,2-trifluorotrichloroethane (100 ml) and the mixture was heated under reflux for ca 16 hr. The solvent was removed by distillation and unbrominated starting material was removed by acetylation as described in Example 1(b) to yield 4-(5-bromo-3-methyl-2-pyridyl)-butylamine (6.53 g) as an oil.

Source