Reaction #685010

Reaction equation

pentan-2-one

3-(4-chlorophenyl)-3-oxopropanenitrile

β-alanine

acetic acid

→

crude residue

2-(4-chlorobenzoyl)-3-methylhex-2-enenitrile

Solvents

toluene

EtOAc

Conditions

Workup

1. 1
   Temperatureis heated
2. 2
   Temperatureto reflux in a Dean-Stark system for 18 h
3. 3
   Washwashed with 5% NaHCO3 (3×20 mL), water (20 mL), brine (20 mL)
4. 4
   Dryingdried (Na2SO4)
5. 5
   Concentrationfinally concentrated in vacuo
6. 6
   workup.ADDITIONA mixture of the two isomers

Procedure

A mixture of pentan-2-one (20 mmol), 3-(4-chlorophenyl)-3-oxopropanenitrile (3.6 g, 20 mmol), β-alanine (180 mg, 2 mmol), acetic acid (2.6 mL) and toluene (60 mL) is heated to reflux in a Dean-Stark system for 18 h. The solution is cooled to RT, then diluted with EtOAc (50 mL), washed with 5% NaHCO3 (3×20 mL), water (20 mL), brine (20 mL), dried (Na2SO4) and finally concentrated in vacuo. A mixture of the two isomers is obtained as a colorless oil by chromatographic purification of the crude residue on silica gel using EtOAc:petroleum ether (0.5:9.5) as eluent.

Source