3,4-dihydro-2H-pyran → Purine

Participants

Reaction Steps

In a 100 ml three-mouth bottle, 2,6-dichloropurine (10 g), ethyl acetate (50 ml), pyridinium salt of paratoluenesulfonic acid (0.2 g) are mixed. The above mixture is stirred and heated to a temperature of 35° C., 2,3-dihydropyrane (12 ml) is added thereto within 5 min. The reaction mixture is reacted at 50˜60° C. for 3 h. The completion of reaction is checked with TCL analysis. Methylamine hydrochloride (4.6 g) is added to the bottle, and then triethylamine (21 ml) is added thereto at the temperature within 30 min, and the above mixture is reacted at the temperature for 1 h. The completion of reaction is checked with TCL analysis. The reaction mixture is cooled to room temperature. After filtration, a filter cake is completely washed with ethyl acetate, and a filtrate is washed with water for 3 times and delaminated. Organic layer is concentrated till large amounts of solid is separated out. After filtration, a filter cake is washed with ethyl acetate for 3 times and then dried in vacuum at 50° C. for 5 h to obtain solid purin (11.0 g). The yield is about 77.7%.

Provenance & Evidence