Phosphorus oxychloride → HCID 19022408, compound

HRID 1109333Notes

Reaction equation

HRID 1109333 reaction equation
O[C:2]1[CH:7]=[C:6]([C:8]([F:11])([F:10])[F:9])[N:5]2[N:12]=[CH:13][C:14]([C:15]([O:17][CH3:18])=[O:16])=[C:4]2[N:3]=1.P(Cl)(Cl)([Cl:21])=O>CN(C)C1C=CN=CC=1>[Cl:21][C:2]1[CH:7]=[C:6]([C:8]([F:11])([F:10])[F:9])[N:5]2[N:12]=[CH:13][C:14]([C:15]([O:17][CH3:18])=[O:16])=[C:4]2[N:3]=1

Participants

4

Procedure

A mixture of 2.70 g of methyl 5-hydroxy-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine-3-carboxylate and 1.26 g of 4-dimethylaminopyridine was heated to 100° for 2.5 hours in 50 ml of phosphorus oxychloride. The resulting solution was concentrated in a vacuum and then partitioned between ethyl acetate and saturated sodium chloride solution. The organic phase was washed in succession with 1N hydrochloric acid and saturated sodium chloride solution, dried over sodium sulphate, freed from solvent in a vacuum and the residue was crystallized from ethyl acetate/petroleum ether. There was obtained methyl 5-chloro-7-(tri-fluoromethyl)pyrazolo[1,5-a]pyrimidine-3-carboxylate as white crystals of m.p. 126-127°.

Workup

  1. concentrationThe resulting solution was concentrated in a vacuum
  2. custompartitioned between ethyl acetate and saturated sodium chloride solution
  3. washThe organic phase was washed in succession with 1N hydrochloric acid and saturated sodium chloride solution
  4. dry with materialdried over sodium sulphate
  5. customthe residue was crystallized from ethyl acetate/petroleum ether

Sources & evidence

ORD record
ord-961d8a156ce6404796f75801d2d6f842
Source dataset
uspto-grants-1994_06
Patent number
US05319140

Reaction notes

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