Reaktion #1536696

Reaktionsgleichung

3-methyl-6,7-dihydro-5H-thiazolo[3,2-a]pyrimidine-2-carboxylic acid hydrochloride

3-Methyl-6,7-dihydro-5H-thiazolo[3,2-a]pyrimidine-2-carboxylic acid hydrochloride

diethylether

→

3-methyl-6,7-dihydro-5H-thiazolo[3,2-a]pyrimidine-2-carbonylchloridehydrochloride

Ausbeute 198.4%

Lösungsmittel

thionylchloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturby reflux
2. 2
   Temperaturunder heating for 30 minutes
3. 3
   workup.DISSOLUTIONAfter dissolving completely
4. 4
   Temperaturthe reaction mixture was cooled
5. 5
   Temperaturunder cooling with ice
6. 6
   FiltrationThe formed crystals were collected by filtration
7. 7
   Sonstigedried over under reduced pressure

Vorschrift

In 75 ml of thionylchloride was suspended 10.0 g of 3-methyl-6,7-dihydro-5H-thiazolo[3,2-a]pyrimidine-2-carboxylic acid hydrochloride obtained in Example 27, followed by reflux under heating for 30 minutes. After dissolving completely, the reaction mixture was cooled. To the reaction mixture was added anhydrous diethylether under cooling with ice. The formed crystals were collected by filtration and dried over under reduced pressure to yield 10.7 g of 3-methyl-6,7-dihydro-5H-thiazolo[3,2-a]pyrimidine-2-carbonylchloridehydrochloride. In 5 ml of pyridine were dissolved 490 mg of this crystal and 0.2 ml of 3,5-dimethylaniline, followed by stirring at room temperature for 6 hours. The reaction mixture was concentrated and to the concentrate was added 5% sodium hydrogencarbonate aqueous solution. The precipitated crystals were collected by filtration and washed with diethylether. The resulting powder was suspended in diethylether. To the suspension was added 0.5 ml of saturated hydrogenchloride aqueous solution, followed by stirring at room temperature. The precipitated crystals were collected by filtration. The crystals were recrystallized from ethanol to obtain 216 mg of the titled compound.

Quelle