Formic Acid → 3H-1,2,4-Triazol-3-one

HRID 1651297노트

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HRID 1651297 반응식
[NH2:1][C:2]([NH2:4])=[O:3].Cl.C(O)=O.[NH2:9][NH:10][C:11]([NH2:13])=[O:12]>>[NH2:9][NH:10][C:11]([NH2:13])=[O:12].[N:4]1[C:2](=[O:3])[N:1]=[CH:11][N:10]=1

참가 물질

6

반응물 4

HCID 284Formic AcidHCID 313Hydrochloric AcidHCID 1176UreaHCID 5196Semicarbazide

생성물 2

HCID 5196SemicarbazideHCID 110733393H-1,2,4-Triazol-3-one수율 47.4%

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온도
10 °C

실험 절차

Aqueous semicarbazide free base feedstock (523.8 grams) was prepared from 64 percent N2H4 (4.18 moles) and urea (4.17 moles) by the method of Example 1. Thirty-seven percent hydrochloric acid (205.6 grams, 2.08 moles) and 90 percent formic acid (533.3 grams, 10.44 moles) were successively added to the aqueous semicarbazide free base. The mixture was heated to 107°-110° C. for four hours; a formic acid-H2O azeotrope distilled (610.5 grams), followed by H2O addition (160 ml) and resumption of stripping (107 grams). After cooling to 10° C., the mother liquor was siphoned (307 grams). The crude 1,2,4-triazol-5-one was recrystallized from H2O (760 ml). After cooling to 10° C., the supernatant liquid was siphoned (807 grams) and the product was slurried with an additional 210 ml H2O (10° C.), filtered, and vacuum-dried to give 168.5 grams of 1,2,4-triazol-5-one (1.98 moles, 47.4 percent yield based on N2H4 charged), m.p. 236.5°-8° C. (Cl-, 0.22 percent).

후처리

  1. temperatureThe mixture was heated to 107°-110° C. for four hours
  2. distillationa formic acid-H2O azeotrope distilled (610.5 grams)
  3. additionfollowed by H2O addition (160 ml) and resumption of stripping (107 grams)
  4. customThe crude 1,2,4-triazol-5-one was recrystallized from H2O (760 ml)
  5. temperatureAfter cooling to 10° C.
  6. customwas slurried with an additional 210 ml H2O (10° C.)
  7. filtrationfiltered
  8. customvacuum-dried

출처 및 근거

ORD 기록
ord-9d460c020b874f4aae71b8e7d03fc609
출처 데이터셋
uspto-grants-1990_05
특허 번호
US04927940

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