Isopropanol → 2-Chloro-6-methyl-isonicotinic acid isopropyl ester

Participants

Reaction Conditions

Reaction Steps

To a suspension of 2-chloro-6-methyl-isonicotinic acid (20.0 g, 117 mmol) in isopropanol (80 mL), H2SO4 (5 mL) is added dropwise. The mixture becomes warm (40° C.). The mixture is stirred for 24 h at rt, then at 90° C. for 28 h before the solvent is removed in vacuo. The residue is dissolved in ether (200 mL), washed with sat. aq. NaHCO3-solution (3×50 mL) followed by brine (3×50 mL), dried over Na2SO4, filtered and concentrated to give 2-chloro-6-methyl-isonicotinic acid isopropyl ester (21.0 g) as a colourless oil which slowly crystallises; LC-MS: tR=0.97 min, [M+1]+=214.05.

Provenance & Evidence