Reaction #302867

Reaction equation

carbamate

1H-Pyrido[2,3-d]oxazin-2,4-dione

methyl amine

CO2

→

2-aminonicotinic acid methyl amide

Yield 97.0%

Solvents

dioxane

ethanol

Conditions

Workup

1. 1
   TemperatureAfter cooling down to room temperature
2. 2
   Otherthe formed precipitate is removed by filtration
3. 3
   Concentrationthe filtrate is concentrated to dryness

Procedure

14.96 g (0.09 mol) of 1H-Pyrido[2,3-d]oxazin-2,4-dione was suspended in 138 ml dioxane. The mixture is heated to 40° C. and 17 ml of a 33% solution of methyl amine in ethanol is added dropwise directly into the reaction mixture, to avoid carbamate formation with the evolving CO2. The reaction is allowed to continue for 90 minutes. After cooling down to room temperature, the formed precipitate is removed by filtration and the filtrate is concentrated to dryness. 13.2 g (97%) of 2-aminonicotinic acid methyl amide was isolated (m.p. 140-2° C.).

Source