Formic Acid → HCID 16039065, compound

Participants

Reaction Conditions

Reaction Steps

Into a three-necked flask having an inner volume of 2 L equipped with a stirrer, a thermometer and a dropping funnel, the whole amount of “Aqueous Solution B” obtained above was charged, and cooled down to 10° C. 99% Formic acid (93.27 g, 2.01 mol) was weighed 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 53° C. by heating, and then 30% hydrogen peroxide aqueous solution (162.5 g, 1.43 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 17 hours from completion of the dropping, the reaction liquid was analyzed by HPLC to confirm that conversion ratio of pyridinium 5-bornene-2-sulfonate was 99.0%. 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 7.5 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 (900 g) twice, and the resultant organic layers were combined, washed with water (200 g), and then concentrated under the reduced pressure until the amount of the liquid became 226.9 g. Isopropyl ether (169.5 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 (50 g) at 5° C., and dried at 40° C. for 2 hours under the reduced pressure, to obtain 2-hydroxy-4-oxa-5-thiatricyclo[4.2.1.03,7]nonane 5,5-dioxide (88.8 g, purity: 99.0%, 0.462 mol). It should be noted that, yield of the product from 5-norbornene-2-sulfonyl chloride was 61.5%.

Provenance & Evidence