Reaktion #2467048

Reaktionsgleichung

sodium bicarbonate

diaminomethylenethiourea

Bromine

2-acetyl-6-cyanomethylpyridine

chloride

→

4-(6-cyanomethylpyridin-2-yl)-2-(diaminomethyleneamino)thiazole

Ausbeute 46.5%

Lösungsmittel

methanol

dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe mixture was stirred for 1 hour at 50° C
2. 2
   workup.STIRRINGthe mixture was stirred for 2.5 hours at 50° C
3. 3
   SonstigeThe solvent was removed by concentration in vacuo
4. 4
   workup.ADDITIONTo the residue was added
5. 5
   workup.ADDITIONa mixture of water, tetrahydrofuran and ethyl acetate
6. 6
   WaschenThe separated organic layer was washed with brine
7. 7
   Trocknendried over magnesium sulfate
8. 8
   Sonstigeevaporated in vacuo
9. 9
   SonstigeThe residue was triturated with water

Vorschrift

Bromine (0.64 ml) was added to a mixture of 2-acetyl-6-cyanomethylpyridine (2.0 g) in dioxane (30 ml) and 4N-dioxanichydrogen chloride (3.1 ml) at ambient temperature with stirring, and then the mixture was stirred for 1 hour at 50° C. To the mixture was added the sodium bicarbonate (5.2 g), methanol (30 ml) and diaminomethylenethiourea (2.2 g) at ambient temperature and the mixture was stirred for 2.5 hours at 50° C. The solvent was removed by concentration in vacuo. To the residue was added a mixture of water, tetrahydrofuran and ethyl acetate and the mixture was adjusted to pH 9.5 with potassium carbonate. The separated organic layer was washed with brine, dried over magnesium sulfate and evaporated in vacuo. The residue was triturated with water to give 4-(6-cyanomethylpyridin-2-yl)-2-(diaminomethyleneamino)thiazole (1.5 g).

Quelle