Guanidine Hydrochloride → tert-butyl 2-amino-5H,6H,7H,8H-pyrido[4,3-d]pyrimidine-6-carboxylate

Participants

Reaction Steps

Guanidine hydrochloride 7.07 g (74 mmol) was added at 0° C. to a solution of sodium 1.65 g (74 mmol) in absolute ethanol and stirring was performed for 2 h at RT under nitrogen as inert gas. 60 ml (60 mmol) of this reaction mixture were added to the solution of 3-dimethylaminomethylene-4-oxo-piperidine-1-carboxylic acid tert-butyl ester in 100 ml of absolute ethanol and refluxing was performed for 5 h. After removal of the solvent and purification by means of column chromatography, 2-amino-7,8-dihydro-5H-pyrido[4,3-d]pyrimidine-6-carboxylic acid tert-butyl ester 5.72 g (43% of theoretical) was obtained.

Provenance & Evidence