Diethylamine → Dipropan-2-yl {4-[(N,N-diethylglycyl)oxy]-1,3-dithiolan-2-ylidene}propanedioate

Participants

Reaction Steps

3.8 Grams (0.01 mole) of the diisopropyl ester of 4-chloroacetoxy-1,3-dithiolan-2-ylidene malonic acid obtained in Example 2 was dissolved in 50 ml of tetrahydrofuran. To the resulting solution was added 1.5 g (0.02 mole) of diethylamine, and the resulting mixture was refluxed for 3 hours. After the reaction, the formed diethylamine hydrochloride was removed by filtration, and then the tetrahydrofuran was removed by distillation. The residue was washed with water and then extracted with 1 N--HCl. The extract was neutralized with a dilute aqueous sodium hydroxide solution to form an oily substance. This oily substance was extracted with ether, and the ether extract was washed with water, dried and the freed from the ether by distillation, whereby 3.5 g of crude crystals of the desired product were obtained. Subsequently, the crude crystals were recrystallized from n-hexane to obtain 3.1 g of white crystals, m.p. 70.5°-71° C., yield 74 %.

Provenance & Evidence