Hydrochloric Acid → (2,6-Difluoropyridin-3-yl)boronic acid

HRID 1590802Notes

Reaction equation

HRID 1590802 reaction equation
C([Li])CCC.C(NC(C)C)(C)C.[F:13][C:14]1[CH:19]=[CH:18][CH:17]=[C:16]([F:20])[N:15]=1.C[O:22][B:23](OC)[O:24]C.Cl>C1COCC1.CCOCC.O>[F:13][C:14]1[C:19]([B:23]([OH:24])[OH:22])=[CH:18][CH:17]=[C:16]([F:20])[N:15]=1

Participants

9

Reactant 5

HCID 313Hydrochloric AcidHCID 7912DiisopropylamineHCID 8470Trimethyl borateHCID 739342,6-DifluoropyridineHCID 178418339Butyllithium

Product 1

HCID 2762713(2,6-Difluoropyridin-3-yl)boronic acid

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 3283Diethyl EtherSolventHCID 8028TetrahydrofuranSolvent

Procedure

0.6 m of n-butyllithium are added to 0.6 m of diisopropylamine in 600 ml of THF at -10°. Then the mixture is cooled to -60° to -70° and 0.6 m of 2,6-difluoropyridine are added. The mixture is stirred for further 15 minutes and 0.6 m of trimethylborate is added at -60°. The mixture is allowed to warm to -30° and is hydrolyzed by addition of 170 ml of HCl (25%) and 100 ml of H2O. Ether is added and after customary work-up 2,6-difluoropyridine-3-boronic acid is obtained.

Workup

  1. temperatureThen the mixture is cooled to -60° to -70°
  2. temperatureto warm to -30°

Sources & evidence

ORD record
ord-a4fd3cb2b26e4281a2cf7555147c2a6b
Source dataset
uspto-grants-1993_04
Patent number
US05204477

Reaction notes

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