3-Fluoro-4-nitropyridine synthesis

Yield:-

Reaction Conditions:

with tetrabutyl ammonium fluoride in tetrahydrofuran;dimethyl sulfoxide at 25;

Steps:

1 Example 1
Example 1 (0052) Non-radioactive fluorination of 3-bromo-4-nitropyridine (3): 10 μL of 1 M tetrabutylammonium fluoride (TBAF) solution in THF (10 μmol, 0.5 eq.) was added to a solution of 3-bromo-4-nitropyridine (96%, Aurum Pharmatech, LLC) (20 μmol, 1 eq.) in 500 L of anhydrous dimethylsulfoxide (DMSO) in a 2 mL HPLC vial. The reaction was analyzed by HPLC (conditions A). Retention times: 3-bromo-4-nitropyridine (3)=10.83 min, 3-fluoro-4-nitropyridine=8.38, 3-bromo-4-fluoropyridine (6)=11.76 min. Retention times for the product matched within 0.05 min the reference standard. Identity of the product was confirmed by HR-MS (m/z M⁺ exp.: 174.9423, calc: 174.9433) and ¹H, ¹³C and ¹⁹F NMR. Product amount was calculated from the area under the curve of the HPLC UV1 trace using a calibration curve.

References:

The University of Chicago;Brugarolas, Pedro US2017/355648, 2017, A1 Location in patent:Paragraph 0052

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