Reaction #631986

Reaction equation

3-hydroxy-1-(2,6,6-trimethyl-2-cyclohexen-1-yl)-1-butanone

NEt3

dimethylamino pyridine

benzoylchloride

HCl

→

product

Yield 77.2%

1-methyl-3-oxo-3-(2,6,6-trimethyl-2-cyclohexen-1-yl)propyl Benzoate

Yield 77.2%

Solvents

CH2Cl2

Conditions

Workup

1. 1
   Extractionextracted twice with ether
2. 2
   Washwashed with water, saturated aqueous NaHCO3
3. 3
   DryingFinally, the organic phases were dried over Na2SO4
4. 4
   Concentrationconcentrated at 50-60°/0.03 mbar) and
5. 5
   Otherpurified by flash-chromatography over SiO2 (cyclohexane/AcOEt=97:3)

Procedure

To a solution of 3-hydroxy-1-(2,6,6-trimethyl-2-cyclohexen-1-yl)-1-butanone (4.00 g, 92% pure, 17.5 mmol), NEt3 (3.2 ml, 22.85 mmol) and dimethylamino pyridine (DMAP) (400 mg) in CH2Cl2 (100 ml) was added benzoylchloride (2.43 ml, 20.94 mmol). The reaction medium was stirred for 65 h at room temperature. Then, the mixture was acidified with 5% aqueous HCl and extracted twice with ether and washed with water, saturated aqueous NaHCO3 and then with saturated aqueous NaCl. Finally, the organic phases were dried over Na2SO4, concentrated at 50-60°/0.03 mbar) and purified by flash-chromatography over SiO2 (cyclohexane/AcOEt=97:3). 4.25 g of product were thus obtained (yield: 73%).

Source