Reaction #49656

Reaction equation

HCl water

N-butyl-4-chlorobenzamide

→

n-butyl-4-chlorobenzenemethanamine

Yield 164.6%

Solvents

THF

Conditions

Workup

1. 1
   workup.ADDITIONWhen addition
2. 2
   Temperatureheated
3. 3
   Temperatureto reflux for 3 hours
4. 4
   Temperaturecooled
5. 5
   OtherThe mixture was then evaporated on a rotary evaporator at 60° for 1/2 hour
6. 6
   Extractionextracted with CH2Cl2 (3×25 ml)
7. 7
   WashThe combined extracts were washed with water
8. 8
   Dryingdried (MgSO4)
9. 9
   Filtrationfiltered
10. 10
    Otherevaporated

Procedure

A solution of N-butyl-4-chlorobenzamide (2.26 g; 0.011 mol) in dry THF (25 ml) was added slowly to an ice-cooled solution of 1.0M B2H6 --THF complex (45 ml; 0.045 tool) under a nitrogen blanket. When addition was complete, the mixture was stirred and heated to reflux for 3 hours, cooled and decomposed by dropwise addition of 1:1 conc aq HCl-water (10 ml). The mixture was then evaporated on a rotary evaporator at 60° for 1/2 hour to decompose the boron-amine complexes. The residue was taken up in water, strongly basified with aq NaOH and extracted with CH2Cl2 (3×25 ml). The combined extracts were washed with water, dried (MgSO4), filtered and evaporated to give n-butyl-4-chlorobenzenemethanamine (1.79 g) as an oil. The oil was converted to the hydrochloride salt of the title compound (1.98 g) by crystallising from ethanolic HCl and ethyl acetate, mp 250°-252° after melting and resolidifying at 203°-207° .

Source