1,2-Dibromoethane → Methyl 1-(3-chloro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)cyclopropane-1-carboxylate

HRID 1930142ノート

反応式

HRID 1930142 の反応式
C[Si]([N-][Si](C)(C)C)(C)C.[Li+].[Cl:11][C:12]1[CH:13]=[C:14]([CH2:27][C:28]([O:30][CH3:31])=[O:29])[CH:15]=[CH:16][C:17]=1[B:18]1[O:22][C:21]([CH3:24])([CH3:23])[C:20]([CH3:26])([CH3:25])[O:19]1.Br[CH2:33][CH2:34]Br>C1COCC1>[Cl:11][C:12]1[CH:13]=[C:14]([C:27]2([C:28]([O:30][CH3:31])=[O:29])[CH2:34][CH2:33]2)[CH:15]=[CH:16][C:17]=1[B:18]1[O:22][C:21]([CH3:23])([CH3:24])[C:20]([CH3:25])([CH3:26])[O:19]1

参加物

5

反応物 3

HCID 78391,2-DibromoethaneHCID 2733832Lithium HexamethyldisilazideHCID 58464478Benzeneacetic acid, 3-chloro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-, methyl ester

生成物 1

HCID 59627717Methyl 1-(3-chloro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)cyclopropane-1-carboxylate収率 16.8%

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒

反応条件

温度
0 °C

実験手順

Lithium bis(trimethylsilyl)amide (7.08 mL, 7.08 mmol) was added dropwise to methyl 2-(3-chloro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)acetate (1 g, 3.22 mmol) in THF (20 mL) cooled to 0° C. under nitrogen. The resulting solution was stirred at 0° C. for 30 minutes and then 1,2-dibromoethane (0.305 mL, 3.54 mmol) was added to the reaction and was stirred at 0° C. for 5 minutes. The reaction mixture was quenched with saturated NH4Cl (50 mL) and was diluted with EtOAc (75 mL). The organic layer was separated and re-extracted with EtOAc (75 mL). The combined organics were washed with saturated brine (50 mL), dried (MgSO4), filtered and concentrated to afford crude product. The crude product was purified by flash silica chromatography, elution gradient 0 to 30% EtOAc in isohexane. Pure fractions were evaporated to dryness to afford methyl 1-(3-chloro-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)cyclopropanecarboxylate (0.182 g, 16.79%) as a colourless gum.

後処理

  1. stirringwas stirred at 0° C. for 5 minutes
  2. customThe reaction mixture was quenched with saturated NH4Cl (50 mL)
  3. additionwas diluted with EtOAc (75 mL)
  4. customThe organic layer was separated
  5. extractionre-extracted with EtOAc (75 mL)
  6. washThe combined organics were washed with saturated brine (50 mL)
  7. dry with materialdried (MgSO4)
  8. filtrationfiltered
  9. concentrationconcentrated
  10. customto afford crude product
  11. customThe crude product was purified by flash silica chromatography, elution gradient 0 to 30% EtOAc in isohexane
  12. customPure fractions were evaporated to dryness

出典と根拠

ORDレコード
ord-aca28f8174904daf9dbf40873bdfce0a
出典データセット
uspto-grants-2012_05
特許番号
US08188092B2

反応ノート

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