反応 #75069

反応方程式

2-(2',4'-dimethylphenyl)-5,5-dimethyl-1,3-cyclohexanedione

pyridine

2-ethylhexanoyl chloride

→

3-(2-ethylhexanoyloxy)-5,5-dimethyl-2-(2',4'-dimethylphenyl)-2-cyclohexenone

収率 51.0%

溶媒

chloroform

反応条件

後処理

1. 1
   その他to give 1.58 g of a slightly yellow, viscous oil
2. 2
   その他This material was chromatographed through 75 g of silica gel (0.063-0.2 mm)

実験手順

A solution of 1.50 g (6.14 mmol) of 2-(2',4'-dimethylphenyl)-5,5-dimethyl-1,3-cyclohexanedione in 10 ml of chloroform was cooled in ice and 1.94 g (24.56 mmol) of pyridine added followed by 2.00 g (12.28 mmol) of 2-ethylhexanoyl chloride. The mixture was stirred for 2 hrs. at room temperature, then refluxed for 12 hrs. The mixture was worked up exactly as described in Example I above to give 1.58 g of a slightly yellow, viscous oil. This material was chromatographed through 75 g of silica gel (0.063-0.2 mm) using a gradient ranging from 98:2 to 90:10 hexane-ethyl acetate. The chromatography gave 1.15 g (51%) of 3-(2-ethylhexanoyloxy)-5,5-dimethyl-2-(2',4'-dimethylphenyl)-2-cyclohexenone as a clear colorless oil which showed one spot on a thin layer chromatogram (70:30 hexane-ethyl acetate) at Rf=0.52.

出典