Diisopropylamine → (2-Methoxypyridin-3-yl)boronic acid

HRID 643000Notes

Reaction equation

HRID 643000 reaction equation
C(NC(C)C)(C)C.[Li]CCCC.[CH3:13][O:14][C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][N:16]=1.[B:21](OC(C)C)([O:26]C(C)C)[O:22]C(C)C>C1COCC1.O>[CH3:13][O:14][C:15]1[C:20]([B:21]([OH:26])[OH:22])=[CH:19][CH:18]=[CH:17][N:16]=1

Participants

7

Reactant 4

HCID 7912DiisopropylamineHCID 21531Triisopropyl borateHCID 742012-MethoxypyridineHCID 178418339Butyllithium

Product 1

HCID 2762709(2-Methoxypyridin-3-yl)boronic acidYield 40%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
0 °C

Procedure

To a solution of diisopropylamine (1.42 mL, 10 mmol) in THF (10 mL) at 0° C. was added nBuLi (2.5 M, 4.25 mL, 10.6 mmol) dropwise. After stirring at 0° C. for 45 min, a solution of 2-methoxypyridine (0.96 mL, 9.2 mmol) in THF (5 mL) was added, and the mixture was stirred for an additional 1 h before B(OiPr)3 (2.54 mL, 11 mmol) was added. 30 min later, H2O was added to quench the reaction, the THF was removed in vacuo and the aqueous layer was extracted with ether. The aqueous layer was separated, acidified with 48% HBr to pH=4, the resulting precipitates were collected by filtration to yield 2-methoxypyridine-3-ylboronic acid (0.46 g, 40%).

Workup

  1. additionwas added
  2. customto quench
  3. customthe reaction
  4. customthe THF was removed in vacuo
  5. extractionthe aqueous layer was extracted with ether
  6. customThe aqueous layer was separated
  7. customthe resulting precipitates
  8. filtrationwere collected by filtration

Sources & evidence

ORD record
ord-d838477117c64aad8aa73c342c1b4190
Source dataset
uspto-grants-2010_04
Patent number
US07696352B2

Reaction notes

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