Formamidine acetate → 1H-pyrido[3,4-d]pyrimidin-4-one

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-amino-isonicotinic acid (32)(26.24 g, 190.0 mmol) and formamidine acetate (39.56 g, 380 mmol) in dimethylacetamide (100 ml) was stirred and heated to 150° C. The reaction was maintained at this temperature with stirring for 12 hours before it was allowed to cool to 25° C. and then basified with sodium bicarbonate solution (5% aqueous) until pH 7-8 was attained. The resultant pale brown solid was removed by filtration, washed with water (20 ml) and dried in a desiccator to give the desired compound (24.50 g, 87.63%) which required no further purification. m/z (LC-MS, ESP): 148 [M+H]+, R/T=1.09 mins.

Provenance & Evidence