Pinacol → 5-(1,3-Dioxolan-2-yl)-2-fluoro-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine

HRID 1621733

Reaction equation

HRID 1621733 reaction equation
[O:1]1[CH2:5][CH2:4][O:3][CH:2]1[C:6]1[CH:7]=[C:8]([B:13]([OH:15])[OH:14])[C:9]([F:12])=[N:10][CH:11]=1.S([O-])([O-])(=O)=O.[Mg+2].O[C:23]([C:26](O)([CH3:28])[CH3:27])([CH3:25])[CH3:24]>C1(C)C=CC=CC=1>[O:1]1[CH2:5][CH2:4][O:3][CH:2]1[C:6]1[CH:7]=[C:8]([B:13]2[O:15][C:26]([CH3:28])([CH3:27])[C:23]([CH3:25])([CH3:24])[O:14]2)[C:9]([F:12])=[N:10][CH:11]=1

Participants

5

Reactant 3

HCID 6425PinacolHCID 24083Sulfuric acid magnesium salt (1:1)HCID 595483675-(1,3-Dioxolan-2-yl)-2-fluoropyridin-3-ylboronic acid

Product 1

HCID 595484325-(1,3-Dioxolan-2-yl)-2-fluoro-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridineYield 95.1%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

5-(1,3-Dioxolan-2-yl)-2-fluoropyridin-3-ylboronic acid (14.56 g, 68.4 mmol) was suspended in PhMe (300 mL) and anhydrous magnesium sulfate (41.223 g, 342 mmol) and pinacol (8.27 g, 70.0 mmol) were added. The reaction was stirred under nitrogen at room temperature over the weekend. The suspension was filtered, and the solid was washed with EtOAc. The filtrate was washed with brine (2×200 mL), and the organic phase was dried over sodium sulfate, filtered, concentrated and dried to give 19.19 g of 5-(1,3-dioxolan-2-yl)-2-fluoro-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine as a light yellow powder. 1H NMR (CDCl3, 400 MHz) δ 8.39 (d, J=2.54 Hz, 1H); 8.28 (dd, J=8.02 Hz, 2.54 Hz, 1H); 5.84 (s, 1H); 4.17-4.04 (m, 4H); 1.37 (s, 12H).

Workup

  1. filtrationThe suspension was filtered
  2. washthe solid was washed with EtOAc
  3. washThe filtrate was washed with brine (2×200 mL)
  4. dry with materialthe organic phase was dried over sodium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated
  7. customdried

Sources & evidence

ORD record
ord-2e67ef38d94c491a9462b0006544f1c4
Source dataset
uspto-grants-2014_07
Patent number
US08772480B2

Linked notes

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