Hydrochloric Acid → 1-(8-Diethylamino-5-hydroxy-5-methyl-6-octynyl)-3-methyl-7-propylxanthine

Participants

Reaction Conditions

Reaction Steps

32.4 ml (52 mmol) of a 1.6 M solution of n-butyllithium in n-hexane was added dropwise in 30 minutes to 5.8 g (52 mmol) of N,N-diethyl-2-propynylamine from stage C1) dissolved in 40 ml of tetrahydrofuran at between -60° C. and -65° C. The mixture was stirred at -70° C. for one hour and then warmed to room temperature, and a solution of 12.3 g (40 mmol) of 3-methyl-1-(5-oxohexyl)-7-propylxanthine in 60 ml of tetrahydrofuran was added dropwise over the course of 20 minutes, during which the temperature of the reaction mixture rose to 35° C. After stirring at room temperature for four hours, 100 ml of cold 1 N hydrochloric acid were added, the mixture was extracted by shaking several times with dichloromethane, the aqueous phase was made alkaline with sodium carbonate, the reaction product was extracted with dichloromethane, and drying of the sodium sulfate was followed by concentration under reduced pressure. The oily residue was purified by filtration through a silica gel column in chloroform/methanol (19:1) as eluent.

Provenance & Evidence