Hydrochloric Acid → 1,2,5-Oxadiazole-3,4-dicarbonyl dichloride

HRID 328667Notes

Reaction equation

HRID 328667 reaction equation
S(Cl)([Cl:3])=O.[O:5]1[N:9]=[C:8]([C:10](O)=[O:11])[C:7]([C:13]([OH:15])=O)=[N:6]1.[ClH:16]>CN(C)C=O>[O:5]1[N:9]=[C:8]([C:10]([Cl:16])=[O:11])[C:7]([C:13]([Cl:3])=[O:15])=[N:6]1

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 24386Thionyl ChlorideHCID 14190971,2,5-oxadiazole-3,4-dicarboxylic acid

Product 1

HCID 214397041,2,5-Oxadiazole-3,4-dicarbonyl dichloride

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

In a glass reactor under a blanket of nitrogen was placed 120 ml of thionyl chloride and 15.8 g of 1,2,5-oxadiazole-3,4-dicarboxylic acid (Grundmann, Ber. 97 (2), 575-8, 1964). The mixture was heated to reflux and 0.5 ml of dimethylformamide was added. In the ensuing vigorous reaction HCl and SO2 were given off. Refluxing was continued for about 1 hour until all the free acid was dissolved. Excess thionyl chloride was removed at 50° C under vacuum and the residue distilled at 35° C/0.5 mm. Two redistillations gave 13.5 g of 1,2,5-oxadiazole-3,4-dicarbonyl chloride in the form of a colorless liquid boiling at 62°-64° C/9 mm. Infrared absorption at 1760 cm-1 (C=O) and at 1525 cm-1 and 1440 cm-1 (-C=N) was consistent with the proposed structure.

Workup

  1. customIn a glass reactor under a blanket of nitrogen was placed
  2. temperatureThe mixture was heated
  3. temperatureto reflux
  4. temperatureRefluxing
  5. dissolutionthe free acid was dissolved
  6. customExcess thionyl chloride was removed at 50° C under vacuum
  7. distillationthe residue distilled at 35° C/0.5 mm

Sources & evidence

ORD record
ord-3043527c130a476abeed154966af9c9a
Source dataset
uspto-grants-1977_04
Patent number
US04018748

Reaction notes

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