Acetone → 4-(1-Hydroxy-1-methyl-ethyl)-3-methyl-benzoic acid

HRID 1478454

反応式

HRID 1478454 の反応式
Br[C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[CH:4][C:3]=1[CH3:11].C([Li])CCC.[CH3:17][C:18]([CH3:20])=[O:19].Cl>O1CCCC1.[OH-].[Na+]>[OH:19][C:18]([C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[CH:4][C:3]=1[CH3:11])([CH3:20])[CH3:17]

参加物

7

反応物 4

HCID 180AcetoneHCID 313Hydrochloric AcidHCID 821314-Bromo-3-methylbenzoic acidHCID 178418339Butyllithium

生成物 1

HCID 681532454-(1-Hydroxy-1-methyl-ethyl)-3-methyl-benzoic acid収率 42.3%

試薬・触媒・溶媒 2

HCID 8028Tetrahydrofuran溶媒HCID 14798Sodium Hydroxide溶媒

反応条件

温度
-78 °C

実験手順

4-Bromo-3-methyl-benzoic acid (3.96 g, 18.4 mmol) was dissolved in tetrahydrofuran (100 mL) and the solution was cooled to −78° C. n-Butyllithium in hexanes (16.2 mL of 2.5 M, 41 mmol) was added dropwise over 20 minutes. The reaction mixture was allowed to stir for 30 minutes at −78° C. and then acetone (1.35 mL, 18.4 mmol) was added in a drop-wise manner. The reaction mixture was allowed to stir for 30 minutes at −78° C., and then it was allowed to warm to room temperature. The reaction mixture was then diluted with 100 mL of 1M aqueous sodium hydroxide. The organic layer was discarded and then the aqueous layer was made acidic with 4M aqueous hydrochloric acid. The aqueous layer was then extracted 3 times with ethyl acetate. The combined extracts were dried over sodium sulfate and then evaporated to dryness. The crude material was further purified on silica gel utilizing a gradient of 0-10% methanol in dichloromethane to give 4-(1-hydroxy-1-methyl-ethyl)-3-methyl-benzoic acid (1.51 g, 42%). 1H NMR (400 MHz, DMSO) δ 12.74 (s, 1H), 7.68 (dd, J=3.9, 2.5 Hz, 2H), 7.55 (d, J=8.7 Hz, 1H), 5.06 (s, 1H), 2.56 (s, 3H), 1.51 (s, 6H).

後処理

  1. additionwas added dropwise over 20 minutes
  2. stirringto stir for 30 minutes at −78° C.
  3. temperatureto warm to room temperature
  4. extractionThe aqueous layer was then extracted 3 times with ethyl acetate
  5. dry with materialThe combined extracts were dried over sodium sulfate
  6. customevaporated to dryness
  7. customThe crude material was further purified on silica gel utilizing a gradient of 0-10% methanol in dichloromethane

出典と根拠

ORDレコード
ord-c5adf216169d43a4988c0ef2f93064ec
出典データセット
uspto-grants-2016_08
特許番号
US09403839B2

関連ノート

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