Formic Acid → HCID 16039065, compound

Temperature

10 °C

Into a three-necked flask having an inner volume of 300 mL equipped with a stirrer, a thermometer and a dropping funnel, the whole amount of “Aqueous Solution D” obtained above was charged, and cooled down to 10° C. 99% Formic acid (10.8 g, 0.232 mol) was weighed into a dropping funnel, and added dropwise to the reaction system so that the inner temperature of the reaction system was maintained in a range of 11 to 15° C. After that, the inner temperature was raised up to 50 to 52° C. by heating, and then 30% hydrogen peroxide aqueous solution (18.69 g, 0.165 mol) weighed and contained in another dropping funnel was added dropwise to the reaction system over 3 hours. After completion of the dropping, the inner temperature of the reaction system was also maintained at around 50° C. After 21 hours from completion of the dropping, the reaction liquid was analyzed by HPLC to confirm that conversion ratio of 2,6-dimethylpyridinium 5-bornene-2-sulfonate was 98.4%. After cooling down the reaction liquid to 15° C., sodium sulfite was added slowly to the reaction system so that the inner temperature of the reaction system was maintained in a range of 15 to 18° C. until a starch paper did not detect hydrogen peroxide. Subsequently, sodium hydrogen carbonate was added slowly to adjust pH of the reaction liquid at 7.0 so that the inner temperature of the reaction system was maintained in a range of 17 to 20° C. The reaction liquid was extracted with ethyl acetate (100 g) twice, the resultant organic layers were combined, and washed with water (25 g), then concentrated under the reduced pressure until the amount of the liquid became 37.4 g. Isopropyl ether (21.0 g) was added to the resultant concentrated liquid in a heated state at 50° C., then the mixture was cooled down to 5° C. at a rate of about 10° C./hour, to precipitate crystal of the product. After filtering the precipitated crystal, the filtered out crystal was washed with isopropyl ether (6.0 g) at 5° C., and dried at 40° C. for hours under the reduced pressure, to obtain 2-hydroxy-4-oxa-5-thiatricyclo[4.2.1.03,7]nonane 5,5-dioxide (7.86 g, purity: 98.1%, 0.041 mol). It should be noted that, yield of the product from 5-norbornene-2-sulfonyl chloride was 46.8%.

1. customInto a three-necked flask having
2. customan inner volume of 300 mL equipped with a stirrer
3. additionwas charged
4. additionadded dropwise to the reaction system so that the inner temperature of the reaction system
5. temperaturewas maintained in a range of 11 to 15° C
6. temperatureAfter that, the inner temperature was raised up to 50 to 52° C.
7. temperatureby heating
8. customcontained in another dropping funnel
9. additionwas added dropwise to the reaction system over 3 hours
10. temperatureAfter completion of the dropping, the inner temperature of the reaction system was also maintained at around 50° C
11. customthe reaction liquid
12. temperatureAfter cooling down
13. customthe reaction liquid to 15° C.
14. custompH of the reaction liquid at 7.0 so that the inner temperature of the reaction system
15. temperaturewas maintained in a range of 17 to 20° C
16. customThe reaction liquid
17. extractionwas extracted with ethyl acetate (100 g) twice
18. washwashed with water (25 g)
19. concentrationconcentrated under the reduced pressure until the amount of the liquid
20. additionIsopropyl ether (21.0 g) was added to the resultant
21. concentrationconcentrated liquid in a heated state at 50° C.
22. temperaturethe mixture was cooled down to 5° C. at a rate of about 10° C./hour
23. customto precipitate crystal of the product
24. filtrationAfter filtering the precipitated crystal
25. filtrationthe filtered out crystal
26. washwas washed with isopropyl ether (6.0 g) at 5° C.
27. customdried at 40° C. for hours under the reduced pressure

ORD record

ord-6bca428850614419b41d36c614782a65

Source dataset

uspto-grants-2013_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08367849B2