Formic Acid → 3H-1,2,4-Triazol-3-one

HRID 1651297ノート

反応式

HRID 1651297 の反応式
[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

参加物

6

反応物 4

HCID 284Formic AcidHCID 313Hydrochloric AcidHCID 1176UreaHCID 5196Semicarbazide

生成物 2

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

反応条件

温度
10 °C

実験手順

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).

後処理

  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

出典と根拠

ORDレコード
ord-9d460c020b874f4aae71b8e7d03fc609
出典データセット
uspto-grants-1990_05
特許番号
US04927940

反応ノート

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