Thionyl Chloride → HCID 19978165, compound

Participants

Reaction Steps

To 20 ml of thionyl chloride was suspended 5.0 g of 3-cyclobutyl-6,7-dihydro-5H-thiazolo[3,2-a]pyrimidine-2-carboxylic acid obtained in Example 1, followed by reflux under heating for 30 minutes. Under cooling, an anhydrous diethylether was added dropwise to the reaction mixture to precipitate. The crystals were collected by filtration and washed with anhydrous diethylether to yield 5.4 g of 3-cyclobutyl-6,7-dihydro-5H-thiazolo[3,2-a]pyrimidine-2-carbonyl chloride as a pale yellow crystals. To the mixture of 60 ml of pyridine and 20 ml of dimethyl formamide was suspended 2.7 g of the crystal. To the mixture was added 1.5 g of 3,5-dichloroaniline and 60 mg of dimethylaminopyridine, followed by stirring at 70° C. for 17 hours. The solvent was removed under reduced pressure to obtain a residue. Addition of water to the residue caused precipitation of the crystals and the crystals were collected by filtration. After washing with cold methanol, the crystals were suspended to saturated hydrogenchloride ethanol solution. After washing with diethylether, the crystals were collected by filtration to obtain 1.2 g of the titled compound.

Provenance & Evidence