A solution 35.6 g of 4-chlormethyl-6,7-dihydroxycoumarin and 27.3 g of morpholine in 4.5 L methyl ethyl ketone was refluxed for 9 hours. On cooling the morpholine hydrochloride was deleted. Methyl ethyl ketone was evaporated in vacuum. The solid product was mixed with 500 ml of water and dried in vacuum with P2O5. Yield of crude 6,7-dihydroxy-4(morpholinomethyl)coumarin is 41.5 g. After recrystallization from ethanol was obtained 6,7-dihydroxy-4-(morpholinomethyl)coumarin with M.P. 232°C.
In practice it is usually used as hydrochloride.
