反応 #93556

反応方程式

2-diazo-5,5-dimethylcyclohexane-1,3-dione

chlorobenzene

benzophenone

5-t-butyl-m-xylene

→

2-(2',6'-dimethyl-4'-t-butylphenyl)-5,5-dimethyl-1,3-cyclohexanedione

収率 11.0%

反応条件

後処理

1. 1
   その他fitted with a borosilicate glass
2. 2
   ろ過filter
3. 3
   その他after degassing for 1 hour under nitrogen
4. 4
   抽出The photolysis mixture was extracted with 0.25N NaOH
5. 5
   洗浄washed with ether
6. 6
   抽出extracted with chloroform
7. 7
   乾燥The chloroform was dried over anhydrous MgSO4
8. 8
   その他to give a crude yellow solid
9. 9
   その他the combined crude product from these reactions was chromatographed through silica gel (0.063-0.2 mm)
10. 10
    その他The solid obtained from the chromatography
11. 11
    その他was recrystallized from benzene

実験手順

A solution of 7.00 g (0.042 mol) of 2-diazo-5,5-dimethylcyclohexane-1,3-dione in 300 ml of 5-t-butyl-m-xylene and 250 ml chlorobenzene containing 38.38 g (0.21 mol) of benzophenone was irradiated overnight with a 200 watt mercury arc lamp fitted with a borosilicate glass filter after degassing for 1 hour under nitrogen. The photolysis mixture was extracted with 0.25N NaOH, washed with ether, acidified with 1N HCl, and extracted with chloroform. The chloroform was dried over anhydrous MgSO4 and stripped to give a crude yellow solid. The photolysis was repeated and the combined crude product from these reactions was chromatographed through silica gel (0.063-0.2 mm) using benzene-ethyl acetate. The solid obtained from the chromatography was recrystallized from benzene to give 2.76 g (11%) of 2-(2',6'-dimethyl-4'-t-butylphenyl)-5,5-dimethyl-1,3-cyclohexanedione as white crystals, mp 244°-49° C.

出典