Acetyl chloride → 1-Methyl-4-oxo-5-pentylcyclopent-2-EN-1-YL acetate

Reaction equation

[OH:1][C:2]1([CH3:13])[CH:6]=[CH:5][C:4](=[O:7])[CH:3]1[CH2:8][CH2:9][CH2:10][CH2:11][CH3:12].C(N(CC)CC)C.[C:21](Cl)(=[O:23])[CH3:22]>C(Cl)(Cl)Cl>[C:21]([O:1][C:2]1([CH3:13])[CH:6]=[CH:5][C:4](=[O:7])[CH:3]1[CH2:8][CH2:9][CH2:10][CH2:11][CH3:12])(=[O:23])[CH3:22]

Participants

Procedure

Into the same flask as in Example 1, 3-hydroxy-2-n-pentyl-3-methyl-4-cyclopentenone (18.2 g), triethylamine (20.3 g) and chloroform (150 g) were charged, and acetyl chloride (15.8 g) was dropwise added thereto at a temperature of 10° to 15° C. in 2 hours. Then, stirring was continued at room temperature for 20 hours. The reaction mixture was treated as in Example 1. The residue was purified by silica gel chromatography using a mixture of toluene and ethyl acetate (10:1) as an eluent to give dl-3-acetoxy-2-n-pentyl-3-methyl-4-cyclopentenone (21.5 g). Yield, 96%.