Phosphoric Acid → [3-({[(1,1-Dimethylethyl)(dimethyl)silyl]oxy}methyl)phenyl]boronic acid

HRID 657349Notes

Reaction equation

HRID 657349 reaction equation
Br[C:2]1[CH:3]=[C:4]([CH2:8][O:9][SiH:10]([CH3:12])[CH3:11])[CH:5]=[CH:6][CH:7]=1.C[C:14]([CH3:17])([CH3:16])[CH3:15].[Li]CCCC.[B:23](OCCCC)([O:29]CCCC)[O:24]CCCC.OP(O)(O)=O>C1COCC1>[CH3:15][C:14]([Si:10]([CH3:12])([CH3:11])[O:9][CH2:8][C:4]1[CH:3]=[C:2]([B:23]([OH:29])[OH:24])[CH:7]=[CH:6][CH:5]=1)([CH3:17])[CH3:16]

Participants

6

Reactant 4

HCID 1004Phosphoric AcidHCID 12712Tributyl borateHCID 137331256{[(3-Bromophenyl)methyl]oxy}(dimethyl)silane 2,2-dimethylpropaneHCID 178418339Butyllithium

Product 1

HCID 57813382[3-({[(1,1-Dimethylethyl)(dimethyl)silyl]oxy}methyl)phenyl]boronic acidYield 74.5%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
-78 °C

Procedure

A solution of {[(3-bromophenyl)methyl]oxy}(dimethyl)silane-2,2-dimethylpropane (1:1) (100.0 g, 331.9 mmol) in THF (500 mL) was cooled to −78° C., and then n-BuLi (132.7 mL, 331.9 mmol) was added dropwise. The mixture was stirred for 1 h at −78° C. Then B(OBu)3 (107.5 mL, 398.2 mmol) was added in one portion. The reaction mixture was warmed to room temperature, and stirred over night. After cooling to 0° C., 5% H3PO4 was added to pH=4-5 and the mixture stirred 0.5 h and then filtered. After removing THF, the residue was extracted with Et2O (200 mL×2), and the organic layer was dried over Na2SO4. After removing the solvent, the residue was added to water, and a white solid precipitated which was dried in vacuo to give 65.7 g of [3-({[(1,1-dimethylethyl)-(dimethyl)silyl]oxy}methyl)phenyl]boronic acid (yield: 74.5%). 1H NMR (400 MHz, CDCl3) δ 0.14 (s, 6H), 0.98 (s 9H), 4.88 (s, 2H), 7.49-7.59 (m, 2H), 8.14 (d, J=7.6 Hz, 1H), 8.19 (s, 1H).

Workup

  1. temperatureThe reaction mixture was warmed to room temperature
  2. stirringstirred over night
  3. temperatureAfter cooling to 0° C.
  4. stirringthe mixture stirred 0.5 h
  5. filtrationfiltered
  6. customAfter removing THF
  7. extractionthe residue was extracted with Et2O (200 mL×2)
  8. dry with materialthe organic layer was dried over Na2SO4
  9. customAfter removing the solvent
  10. additionthe residue was added to water
  11. customa white solid precipitated which
  12. customwas dried in vacuo

Sources & evidence

ORD record
ord-008a94b600a44c4390d98dc8598dce00
Source dataset
uspto-grants-2011_12
Patent number
US08071588B2

Reaction notes

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