反应详情

温度

60 °C

A mixture of 0.5 g of (7R,8S,9R)-2,3,8-trimethyl-7,8-dihydroxy-9-phenyl-7,8,9,10-tetrahydroimidazo[1,2-h][1,7]naphthyridine and 0.2 ml of conc. sulfuric acid in 10 ml of 2-methoxyethanol is heated at an oil bath temperature of 60° C. for 24 h and then stirred at room temperature for 40 h. The reaction solution is poured into a mixture of 50 ml of saturated aqueous sodium hydrogencarbonate solution and 50 ml of dichloromethane and vigorously stirred. After separating off the organic phase, the aqueous phase is extracted a further three times with 50 ml of dichloromethane each time, the organic phases are combined, the solvent is stripped off in vacuo and the residue obtained is chromatographed on silica gel (eluent: diethyl ether/diethylamine 1/1). 0.3 g of the title compound is obtained as colorless crystals of melting point 1734° C. (diethyl ether).

1. stirringvigorously stirred
2. customAfter separating off the organic phase
3. extractionthe aqueous phase is extracted a further three times with 50 ml of dichloromethane each time
4. customthe residue obtained
5. customis chromatographed on silica gel (eluent: diethyl ether/diethylamine 1/1)