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

Participants

Reaction Steps

A mixture of methyl 2-chloro-6-[(cyclopentylmethyl)amino]pyrimidine-4-carboxylate (Intermediate 2, 2.00 g; 7.82 mmol; 1.00 eq.), palladium on charcoal (750 mg) and triethylamine (3.27 mL; 23.5 mmol) in EtOH (200 mL) was stirred under an atmosphere of hydrogen for 2 hours. After 2 hours the reaction mixture was filtered on celite and evaporated to give a mixture of methyl 6-(cyclopentylamino)pyrimidine-4-carboxylate and ethyl 6-(cyclopentylamino)pyrimidine-4-carboxylate. The crude mixture was dissolved in a mixture of THF/EtOH/H2O (3/2/1, 120 mL) and treated with an aqueous solution of lithium hydroxide (1N, 23.5 mL, 23.5 mmol). The reaction mixture was stirred at RT for 60 minutes. Water was added (50 mL) and the aqueous layer was washed with DCM (30 mL). The aqueous layer was acidified to pH 5 by addition of an HCl solution (1N). The aqueous layer was evaporated in vacuo to reduce the volume by 30-50%. The resulting white solid was filtered to afford the title compound as a white solid.

Provenance & Evidence