Formic Acid → HCID 59228918, compound

Participants

Reaction Conditions

Reaction Steps

Into a three-necked flask having an inner volume of 500 mL equipped with a stirrer, a thermometer and a dropping funnel, the whole amount of “Concentrated Liquid F” obtained above was charged, and cooled down to 10° C. 99% Formic acid (30.0 g, 0.645 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 15 to 18° C. After that, the inner temperature was raised up to 34 to 35° C. by heating, and then 30% hydrogen peroxide aqueous solution (45.2 g, 0.399 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 35° C. After 40 hours from completion of the dropping, the reaction liquid was analyzed by HPLC to confirm that conversion ratio of sodium 7-oxa-5-bornene-2-sulfonate was 98.1%. After cooling down the reaction liquid to 20° 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 20 to 25° C. until a starch paper did not detect hydrogen peroxide. Subsequently, 30% sodium hydroxide aqueous solution was added slowly to adjust pH of the reaction liquid at 6.8 so that the inner temperature of the reaction system was maintained in a range of 20 to 25° C. The reaction liquid was extracted with ethyl acetate (100 g) three times, and the resultant organic layers were combined, washed with water (50 g), and then concentrated under the reduced pressure until forming of white solid could be seen. Ethyl acetate (20 g) was added, and then isopropyl ether (40 g) as also added in a heated state at 60° C., then the mixture was cooled down to 1° C. at a rate of about 15° C./hour, to precipitate crystal of the product. After filtering the precipitated crystal, the filtered out crystal was washed with isopropyl ether (40 g) at 1° C., and dried at 30° C. for 2 hours under the reduced pressure, to obtain 2-hydroxy-4,8-dioxa-5-thiatricyclo[4.2.1.03,7]nonane 5,5-dioxide (6.84 g, purity: 98.9%, 0.035 mol). It should be noted that, yield of the product from 7-oxa-5-norbornene-2-sulfonyl chloride was 14.2%.

Provenance & Evidence