Lithium Hydroxide → 6-(Cyclohexylamino)pyrimidine-4-carboxylic acid

Participants

Reaction Steps

A mixture of methyl 2-chloro-6-(cyclohexylamino)pyrimidine-4-carboxylate (Intermediate 1, 9.20 g; 34.1 mmol), triethylamine (14.3 mL; 102 mmol) and palladium on charcoal (750 mg) in EtOH (1 L) was stirred at RT under an atmosphere of hydrogen for 16 hours. The reaction mixture was filtered through celite and the solvent was evaporated in vacuo to give a mixture of methyl 6-(cyclohexylamino)pyrimidine-4-carboxylate and ethyl 6-(cyclohexylamino)pyrimidine-4-carboxylate. This crude was dissolved in a mixture of THF/EtOH/H2O (3/2/1, 1 L) and treated with an aqueous lithium hydroxide solution (1N, 102 mmol). After 1 hour, the organic solvents were evaporated in vacuo and water was added. The aqueous layer was washed with DCM (200 mL), then acidified to pH 4 by addition of an HCl solution (1N). The aqueous layer was evaporated to reduce the volume by 30-50%. A white solid appeared and was filtered to afford the title compound as a white solid.

Provenance & Evidence