Benzene → 3-Bromo-2,2-diphenylpropionic acid

HRID 542425

反応式

HRID 542425 の反応式
[Br:1][CH2:2][C:3](=O)[C:4]([OH:6])=[O:5].[CH:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1>S(=O)(=O)(O)O.O>[Br:1][CH2:2][C:3]([C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1)([C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1)[C:4]([OH:6])=[O:5]

参加物

5

反応物 2

HCID 241BenzeneHCID 70684Bromopyruvic Acid

生成物 1

HCID 202086173-Bromo-2,2-diphenylpropionic acid

試薬・触媒・溶媒 2

HCID 962Water溶媒HCID 1118Sulfuric Acid溶媒

実験手順

3-Bromopyruvic acid (170 g) is suspended in cold sulfuric acid (0.85 L) and maintained at 0° C. while benzene (0.255 L) is added over 1.5 hours. The temperature is allowed to warm to 35°-36° C. and then kept at 25° C. for three hours. Pouring over crushed ice (4 L) followed by trituration in cold water and recrystallization from 95% ethanol affords 76 g of 3-bromo-2,2-diphenylpropionic acid (mp 201°-202° C.). This acid (75 g) is suspended in benzene and thionyl chloride (55 ml) is added. After refluxing, the mixture is filtered, and the filtrate affords 40 g of the acid chloride (mp 98°14 100° C.). The acid chloride is added portionwise to aqueous ammonium hydroxide with stirring and left overnight, with filtration yielding 3-bromo-2,2-diphenylpropionamide. The amide (10 g) is added portionwise with stirring to a solution of sodium (1.5 g) in absolute ethanol (0.2 L), and the resulting solution is heated for one hour on a steam bath. Dilution with water affords a solid (mp >310° C.), 2,2-diphenyl azetidin-2-one. The azetidinone (2 g) is heated at reflux in methanol saturated with HCl (50 ml) affording the title compound after crystallization from methanol/ether (mp 207°-208° C.).

後処理

  1. additionis added over 1.5 hours
  2. temperatureto warm to 35°-36° C.
  3. additionPouring
  4. customrecrystallization from 95% ethanol

出典と根拠

ORDレコード
ord-50fb884ea7954a759967e232c858df03
出典データセット
uspto-grants-1987_04
特許番号
US04657898

関連ノート

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