Sulfuric Acid → 4-Amino-3-chloro-6-(4-chlorophenyl)-5-fluoropicolinaldehyde

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-((3-chloro-6-(4-chlorophenyl)-2-(diethoxymethyl)-5-fluoropyridin-4-yl)imino)cyclohexa-2,5-dienone (180 milligrams (mg), 0.401 mmol) and 0.1 molar (M) sulfuric acid (H2SO4; 0.5 mL) in a 1:1 mixture of acetonitrile/water (4 mL) was heated to 80° C. for 1 h. After stirring at room temperature for 2 h, the reaction mixture was added to CH2Cl2 (20 mL). The organic layer was washed with a saturated solution of NaCl and dried (MgSO4), and the solvent was removed leaving 4-amino-3-chloro-6-(4-chlorophenyl)-5-fluoropicolinaldehyde (82 mg, 0.273 mmol, 68% yield) as an off-white solid: mp 166-169° C.; 1H NMR (400 MHz, CDCl3) δ 10.12 (s, 1H), 7.96 (m, 2H), 7.48 (m, 2H), 4.99 (s, 2H); 19F NMR (376 MHz, CDCl3) δ −137.68; ESIMS m/z 285.64 ([M+H]+).

Provenance & Evidence