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 above mixture is reacted at 50˜60° C. for 3 h. The completion of reaction is checked with TCL analysis. Triethylamine (8 ml) is added to the bottle, and piperidine (9.2 ml) is added thereto at the temperature within 20 min. The above mixture is reacted at the temperature for 0.5 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 amount 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 (12.8 g). The yield is about 75.2%.

Provenance & Evidence