Sodium hydride → 5-methoxy-1-(triisopropylsilyl)-1H-pyrrolo[3,2-b]pyridin-6-ylboronic acid

HRID 2378973Notes

Reaction equation

HRID 2378973 reaction equation
[CH3:1][O:2][C:3]1[N:8]=[C:7]2[CH:9]=[CH:10][NH:11][C:6]2=[CH:5][C:4]=1[B:12]([OH:14])[OH:13].[H-].[Na+].Cl[Si:18]([CH:25]([CH3:27])[CH3:26])([CH:22]([CH3:24])[CH3:23])[CH:19]([CH3:21])[CH3:20]>O1CCCC1>[CH3:1][O:2][C:3]1[N:8]=[C:7]2[CH:9]=[CH:10][N:11]([Si:18]([CH:25]([CH3:27])[CH3:26])([CH:22]([CH3:24])[CH3:23])[CH:19]([CH3:21])[CH3:20])[C:6]2=[CH:5][C:4]=1[B:12]([OH:14])[OH:13]

Participants

5

Reactant 3

HCID 24758Sodium hydrideHCID 139400Triisopropylsilyl chlorideHCID 590063605-methoxy-1H-pyrrolo[3,2-b]pyridin-6-ylboronic acid

Product 1

HCID 590063505-methoxy-1-(triisopropylsilyl)-1H-pyrrolo[3,2-b]pyridin-6-ylboronic acidYield 99.4%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a white suspension of 5-methoxy-1H-pyrrolo[3,2-b]pyridin-6-ylboronic acid (500 mg, 2.60 mmol) in tetrahydrofuran (25 mL) was added sodium hydride (281 mg, 11.72 mmol) in several portions at 0° C., the resulting light grey suspension was stirred for 30 min, followed by dropwise addition of chlorotriisopropylsilane (2260 mg, 11.72 mmol) through a syringe over 30 sec. under N2. The mixture, as a suspension, was continued stirring at 0° C. for 2 hr, and the conversion was completed as determined by LC/MS. The reaction was carefully quenched with sat. NH4Cl (10 mL), extracted with Et2O (2×50 mL), the combined organic solution was washed with brine (20 mL), dried (Na2SO4), concentrated on rotary vacuo to afford the expected product, 5-methoxy-1-(triisopropylsilyl)-1H-pyrrolo[3,2-b]pyridin-6-ylboronic acid (900 mg, 99%), as a grey gum. 1H-NMR (500 MHz, CHLOROFORM-D) s ppm 1.11 (d, J=7.63 Hz, 21 H) 1.62-1.72 (m, 3 H) 4.03-4.10 (m, 2 H) 6.67 (d, J=3.36 Hz, 1 H) 7.31 (s, 1 H) 7.43 (d, J=3.05 Hz, 1 H); Mass spec 349.21 (MH+) Calc for C17H29BN2O3Si 348.2.

Workup

  1. stirringThe mixture, as a suspension, was continued stirring at 0° C. for 2 hr
  2. customThe reaction was carefully quenched with sat. NH4Cl (10 mL)
  3. extractionextracted with Et2O (2×50 mL)
  4. washthe combined organic solution was washed with brine (20 mL)
  5. dry with materialdried (Na2SO4)
  6. concentrationconcentrated on rotary vacuo

Sources & evidence

ORD record
ord-3d01dfebdf16448989e19a8088904fcb
Source dataset
uspto-grants-2008_12
Patent number
US07470680B2

Reaction notes

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