반응 #162353

반응 방정식

1,2-diethyl 4-cyanotetrahydro-1,2-pyridazinedicarboxylate

product

1,2-diethyl 4-cyanotetrahydro-1,2-pyridazinedicarboxylate

thioacetamide

→

title compound

1,2-diethyl 4-(aminothioxomethyl)tetrahydro-1,2-pyridazinedicarboxylate

용매

trifluoroacetic acid

반응 조건

후처리

1. 1
   온도The reaction mixture was cooled
2. 2
   기타partitioned between water and diethyl ether (about 30 mL)
3. 3
   기타The layers were separated
4. 4
   추출the aqueous layer was extracted with diethyl ether (2×)
5. 5
   세척The combined organic extracts were washed with water (about 30 mL), dried magnesium sulfate
6. 6
   여과filtered
7. 7
   농축concentrated
8. 8
   기타purified by silica gel column chromatography (25% to 60% gradient of ethyl acetate in petroleum ether as eluant)

실험 절차

A mixture of 1,2-diethyl 4-cyanotetrahydro-1,2-pyridazinedicarboxylate (i.e the product of Step E) (5.5 g, 0.024 mol) and thioacetamide (5.5 g, 0.073 mol) in trifluoroacetic acid (about 10 mL) was heated at 50° C. for 20 h. The reaction mixture was cooled, and then partitioned between water and diethyl ether (about 30 mL). The layers were separated and the aqueous layer was extracted with diethyl ether (2×). The combined organic extracts were washed with water (about 30 mL), dried magnesium sulfate, filtered and concentrated under reduce pressure to an orange oil. The oil was adsorbed onto Celite® (diatomaceous filter aid), and then purified by silica gel column chromatography (25% to 60% gradient of ethyl acetate in petroleum ether as eluant) to provide the title compound as a yellow solid (3.97 g).

출처