Water → 4-Methyl-3-thiopheneboronic acid

HRID 1432570Notes

Reaction equation

HRID 1432570 reaction equation
CC1(C)C(C)(C)[O:5][B:4]([C:9]2[C:13]([CH3:14])=[CH:12][S:11][CH:10]=2)[O:3]1.O>CC(C)=O>[CH3:14][C:13]1[C:9]([B:4]([OH:5])[OH:3])=[CH:10][S:11][CH:12]=1

Participants

4

Reactant 2

HCID 962WaterHCID 162183474,4,5,5-Tetramethyl-2-(4-methylthiophen-3-yl)-1,3,2-dioxaborolane

Product 1

HCID 50839314-Methyl-3-thiopheneboronic acidYield 35.1%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

A solution of 4,4,5,5-tetramethyl-2-(4-methyl-thiophen-3-yl)-[1,3,2]dioxaborolane (3.69 g, 16.47 mmol) in acetone (30 mL) is treated with H2O (30 mL), followed by NaIO4 (7.05 g, 32.95 mmol). The resulting mixture is stirred at rt overnight. The organic solvent is removed in vacuo. The residue is diluted with H2O (50 mL), extracted with EtOAc ((2×100 mL). The organic extracts are combined, dried with Na2SO4, filtered and concentrated. Purification of the crude material by chromatography gives the title compound (0.82 g, 5.78 mmol, 35%). 1H NMR (CDCl3): δ 1.33 (s, 3H), 2.64-2.66 (m, 2H), 7.00-7.02 (m, 1H), 8.27 (d, J=3.0 Hz, 1H). ES-MS (m/z): calcd for C5H7BO2S (M−H)−: 141.0; found: 141.1.

Workup

  1. customThe organic solvent is removed in vacuo
  2. additionThe residue is diluted with H2O (50 mL)
  3. extractionextracted with EtOAc ((2×100 mL)
  4. dry with materialdried with Na2SO4
  5. filtrationfiltered
  6. concentrationconcentrated
  7. customPurification of the crude material by chromatography

Sources & evidence

ORD record
ord-a8a30ceb476343bbae7eb70893bc2549
Source dataset
uspto-grants-2009_11
Patent number
US07612067B2

Reaction notes

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