Bromine → Ethyl 3-bromo-6(4-chlorophenyl)-4-oxo-4H-pyran-2-carboxylate

HRID 1659474

反応式

HRID 1659474 の反応式
[Br:1]Br.[Cl:3][C:4]1[CH:9]=[CH:8][C:7]([CH:10]=[CH:11][C:12](=[O:21])[CH2:13][C:14](=[O:20])[C:15]([O:17][CH2:18][CH3:19])=[O:16])=[CH:6][CH:5]=1>C(Cl)(Cl)Cl>[Br:1][C:13]1[C:12](=[O:21])[CH:11]=[C:10]([C:7]2[CH:8]=[CH:9][C:4]([Cl:3])=[CH:5][CH:6]=2)[O:20][C:14]=1[C:15]([O:17][CH2:18][CH3:19])=[O:16]

参加物

4

反応物 2

HCID 24408BromineHCID 610034Ethyl 6-(4-chlorophenyl)-2,4-dioxo-hex-5-enoate

生成物 1

HCID 15578373Ethyl 3-bromo-6(4-chlorophenyl)-4-oxo-4H-pyran-2-carboxylate

試薬・触媒・溶媒 1

HCID 6212Chloroform溶媒2 回

実験手順

A solution of bromine (7.06 ml) in chloroform (70 ml) was added dropwise to a stirred solution of ethyl 6-(4-chlorophenyl)-2,4-dioxo-hex-5-enoate (19.2 g) in chloroform (300 ml) at 5° to 10° C. The solution was stirred for 30 minutes at room temperature then evaporated to a yellow oil. This crude tribromide was dissolved in dimethylsulphoxide (150 ml), and 1,5-diazabicyclo[4.3.0]non-5-ene (16.9 g) was added at 20° to 25° C. The mixture was stirred for 30 minutes at room temperature then diluted with ice-water (300 ml) to precipitate a sticky brown solid. A solution of this crude product in chloroform was passed down a short column of silica-gel (100 g) and then evaporated. The residual solid was washed with ethyl acetate-petroleum ether 60°-80° C., then recrystallised from ethyl acetate-petroleum ether 60°-80° C. to give the title product as yellow needles (mp 146°-149° C.).

後処理

  1. customthen evaporated to a yellow oil
  2. dissolutionThis crude tribromide was dissolved in dimethylsulphoxide (150 ml)
  3. addition1,5-diazabicyclo[4.3.0]non-5-ene (16.9 g) was added at 20° to 25° C
  4. stirringThe mixture was stirred for 30 minutes at room temperature
  5. additionthen diluted with ice-water (300 ml)
  6. customto precipitate a sticky brown solid
  7. customevaporated
  8. washThe residual solid was washed with ethyl acetate-petroleum ether 60°-80° C.
  9. customrecrystallised from ethyl acetate-petroleum ether 60°-80° C.

出典と根拠

ORDレコード
ord-16414611ef5f4841aa240f846cecd44a
出典データセット
uspto-grants-1981_12
特許番号
US04304728

関連ノート

読み込み中…