Trimethyl borate → (3,5-Dimethoxyphenyl)boronic acid

HRID 43049Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 43049
[Li]C(C)(C)C.[CH3:6][O:7][C:8]1[CH:9]=[C:10](Br)[CH:11]=[C:12]([O:14][CH3:15])[CH:13]=1.[B:17](OC)([O:20]C)[O:18]C>C1COCC1>[CH3:6][O:7][C:8]1[CH:9]=[C:10]([B:17]([OH:20])[OH:18])[CH:11]=[C:12]([O:14][CH3:15])[CH:13]=1

Komponenten

5

Edukt 3

HCID 8470Trimethyl borateHCID 6391871-Bromo-3,5-dimethoxybenzeneHCID 178418306HCID 178418306, Verbindung

Produkt 1

HCID 4374257(3,5-Dimethoxyphenyl)boronic acidAusbeute 73,7 %

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 8028TetrahydrofuranLösungsmittel

Reaktionsbedingungen

Temperatur
-78 °C

Versuchsvorschrift

t-BuLi (1.7 M in pentatne, 63 mL, 106 mmol, 2.1 equiv) was added dropwise to a cold (−78° C.) solution of 3,5-dimethoxy-bromobenzene (11 g, 50.7 mmol) in THF (400 mL), under an argon atmosphere. The yellow mixture si stirred for 45 min at −78° C. Trimethyl borate (20 mL, 179 mmol, 3.5 equiv) was then added. The colorless reaction mixture was allowed to warm to 0° C., quenched by addition of a saturated solution of NH4Cl (5 mL), and concentrated. The residue was diluted with EtOAc/NH4Cl (saturated aqueous solution), and extracted with EtOAc. The organic phase was dried (Na2SO4), filtered and concentrated. The residue was triturated in Et2O to provide 6.8 g of the title compound as a white solid: ESI-MS: 183.1 [M+H]+; tR=2.70 min (System 1).

Aufarbeitung

  1. temperatureto warm to 0° C.
  2. customquenched by addition of a saturated solution of NH4Cl (5 mL)
  3. concentrationconcentrated
  4. additionThe residue was diluted with EtOAc/NH4Cl (saturated aqueous solution)
  5. extractionextracted with EtOAc
  6. dry with materialThe organic phase was dried (Na2SO4)
  7. filtrationfiltered
  8. concentrationconcentrated
  9. customThe residue was triturated in Et2O

Quellen und Nachweise

ORD-Eintrag
ord-61ad4bcb3c7a4f99aa2cbcd1691366af
Quelldatensatz
uspto-grants-2013_09
Patentnummer
US08536175B2

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