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

HRID 1591022Notes

Reaction equation

HRID 1591022 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>[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

7

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 1

HCID 8028TetrahydrofuranSolvent

Procedure

0,6 M of n-butyllithium are added at -10° to 0,6 M of diisopropylamin in 600 ml THF. The mixture is cooled to -70°, 0,6 M of 2,6-difluoropyridin are added and after stirring for 15 minutes 0,6 M of trimethylborate are added at the same temperature. The mixture is allowed to warm up to -30°. Then the borate ester is hydrolysed with dilute HCl, the product extracted with ether, washed, dried and the solvent removed. Thus, 2,6-difluoro-pyridine-3-boronic acid is obtained.

Workup

  1. temperatureThe mixture is cooled to -70°
  2. additionare added at the same temperature
  3. temperatureto warm up to -30°
  4. extractionthe product extracted with ether
  5. washwashed
  6. customdried
  7. customthe solvent removed

Sources & evidence

ORD record
ord-fed9863340604a3c9855936ca2181f73
Source dataset
uspto-grants-1993_04
Patent number
US05205962

Reaction notes

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