3,4-dihydro-2H-pyran → Purine

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. Dimethylamine hydrochloride (7.3 g) is added to the bottle, and triethylamine (22 ml) is added thereto at the temperature within 30 min, the above mixture is further 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 (8.9 g). The yield is about 59.8%.

1. additionis added
2. customThe above mixture is reacted at 50˜60° C. for 3 h
3. customThe completion of reaction
4. additionis added
5. waitat the temperature within 30 min
6. customthe above mixture is further reacted at the temperature for 0.5 h
7. customThe completion of reaction
8. filtrationAfter filtration
9. washa filter cake is completely washed with ethyl acetate
10. washa filtrate is washed with water for 3 times
11. concentrationOrganic layer is concentrated till large amount of solid
12. customis separated out
13. filtrationAfter filtration
14. washa filter cake is washed with ethyl acetate for 3 times
15. customdried in vacuum at 50° C. for 5 h

ORD record

ord-0e3c18b7ca8247438bc24362011f0ad0

Source dataset

uspto-grants-2013_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08580763B2