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:l) after 45 minutes shows no starting material. The cooled reaction mixture is treated with 100 mL of ethanol and 39 mL of 1.25M 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