Ethyl Acetoacetate → 2-hexylthio-7-methyl-5H-1,3,4-thiadiazolo[3,2-a]pyrimidin-5-one
Reaction equation
[NH2:1][C:2]1[S:3][C:4]([S:7][CH2:8][CH2:9][CH2:10][CH2:11][CH2:12][CH3:13])=[N:5][N:6]=1.[C:14](OCC)(=[O:19])[CH2:15][C:16]([CH3:18])=O>O>[CH2:8]([S:7][C:4]1[S:3][C:2]2=[N:1][C:16]([CH3:18])=[CH:15][C:14](=[O:19])[N:6]2[N:5]=1)[CH2:9][CH2:10][CH2:11][CH2:12][CH3:13]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
Seven (7.0) grams of the thus obtained 2-amino-5-hexylthio-1,3,4-thiadiazole and 4.3 g of ethyl acetoacetate were mixed with 8 g of polyphosphoric acid, and the mixture was heated to 130°-150° C. and stirred for 30 minutes. After cooling, water was added to the reaction mixture, and the resulting mixture was extracted with chloroform. The organic layer was washed with a sodium hydrogen carbonate aqueous solution and water respectively, dried over anhydrous sodium sulfate. The solvent was distilled off. The residue was purified by developing on a silica gel column, and eluting with an ethylacetate/n-hexane (1:1) mixture, and thus 7.5 g of 2-hexylthio-7-methyl-5H-1,3,4-thiadiazolo[3,2-a]pyrimidin-5-one was obtained. Refraction index nD20 : 1.6003. Yield 82%.