Reaction #2348117

Reaction equation

1-(2,6,6-trimethylcyclohex-3-enyl)but-2-en-1-one

ethyl diisopropylamine

L-Cystein ethyl ester hydrochloride

→

title compound

Yield 71.0%

Ethyl 2-(4-oxo-4-(2,6,6-trimethylcyclohex-3-enyl)butan-2-ylamino)-3-(4-oxo-4-(2,6,6-trimethylcyclohex-3-enyl)butan-2-ylthio)propanoate

Yield 71.0%

Solvents

EtOH

Conditions

Workup

1. 1
   OtherThe solvent is removed in vacuo
2. 2
   workup.DISSOLUTIONthe residue dissolved in methyl t-butyl ether
3. 3
   WashThe solution is washed with dilute aq. NaCl
4. 4
   Dryingdried over MgSO4
5. 5
   Concentrationconcentrated
6. 6
   OtherThe residue is purified by chromatography on SiO2

Procedure

A solution of 1-(2,6,6-trimethylcyclohex-3-enyl)but-2-en-1-one (83.0 g, 0.50 mol, 2 equiv.), ethyl diisopropylamine (32.3 g, 0.25 mol, 1 equiv.) and L-Cystein ethyl ester hydrochloride (46.5 g, 0.25 mol, 1 equiv.) in EtOH (600 ml) is heated to 60° C. during 44 h. The solvent is removed in vacuo and the residue dissolved in methyl t-butyl ether. The solution is washed with dilute aq. NaCl, dried over MgSO4 and concentrated. The residue is purified by chromatography on SiO2 to yield 85.5 g (71%) of the title compound as orange oil.

Source