反应详情

温度

100 °C

Crude 9-hydroxythioxanthene (9.58 g, 45 mmol) is mixed with ethyl nitroacetate (5.5 mL, 49 mmol) and heated at 100° C. for 1 hour. TLC (SiO2, hexane:2-propanol/3:1) after 45 minutes shows no starting material. The cooled reaction mixture is treated with 100 mL of ethanol and 39 mL of 1.25 M ethanolic potassium hydroxide solution. Ethanol is stripped and the residue taken up in water and extracted with diethyl ether. The aqueous layer is acidified to pH 2 to 3 with 85% phosphoric acid solution and refrigerated overnight. A crystalline solid is collected by filtration and dried at 50° C./10 mm Hg. A total of 8.4 g of the title compound is collected in three crops; mp 111°-115° C.

1. customThe cooled reaction mixture
2. extractionextracted with diethyl ether
3. filtrationA crystalline solid is collected by filtration
4. customdried at 50° C./10 mm Hg
5. customA total of 8.4 g of the title compound is collected in three crops