Glyoxylic Acid → 3-Hydroxybenzofuran-2(3H)-one

HRID 430730ノート

反応式

HRID 430730 の反応式
O[C:2]1[C:3]2[C:8]([C:9]3C=CC=C[C:14]=3[CH:15]=1)=CC=CC=2.[C:16]([OH:20])(=[O:19])[CH:17]=[O:18]>ClCCCl.C1(C)C=CC(S(O)(=O)=O)=CC=1>[OH:18][CH:17]1[C:15]2[CH:14]=[CH:9][CH:8]=[CH:3][C:2]=2[O:19][C:16]1=[O:20]

参加物

5

反応物 2

HCID 760Glyoxylic AcidHCID 102299-Phenanthrol

生成物 1

HCID 145122453-Hydroxybenzofuran-2(3H)-one収率 79.2%

試薬・触媒・溶媒 2

HCID 6101p-Toluenesulfonic acid触媒HCID 111,2-Dichloroethane溶媒

実験手順

4.9 g of 9-hydroxyphenanthrene, 4.1 g of 50% aqueous glyoxylic acid and 0.05 g of p-toluenesulfonic acid are heated for 2 h in 70 ml of 1,2-dichloroethane under a water separator. The precipitated solid is then cooled down, filtered off, washed with cold 1,2-dichloroethane and dried to leave 3.0 g of hydroxybenzofuranone, which is introduced in 20 ml of toluene as initial charge together with 1.5 ml of thionyl chloride and 3 drops of DMF and then gradually heated to 100° C. so that the evolution of HCl and SO2 remains lively, but still controllable. The reaction mixture is subsequently stirred at 100° C. for 1 h. About 20 ml of liquid are then distilled off to remove excess thionyl chloride. The residue is diluted with 10 ml of toluene and admixed at room temperature with 1.7 ml of triethylamine added dropwise. The thick blue reaction mixture is then refluxed for 2 h. The precipitated isoxindigo is filtered off after cooling down to room temperature, freed of the triethylamine hydrochloride by washing with water, dried and recrystallized from dichloromethane/ethanol to leave 1.3 g (47% of theory) of [3,3′]bi[1-oxacyclopenta[l]phenanthrenylidene]-2,2′dione of the formula:

後処理

  1. temperatureThe precipitated solid is then cooled down
  2. filtrationfiltered off
  3. washwashed with cold 1,2-dichloroethane
  4. customdried

出典と根拠

ORDレコード
ord-b538c5b23c9d45a092966bf8d0b8f136
出典データセット
uspto-grants-2001_11
特許番号
US06323267B1

反応ノート

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