Boron tribromide → 2,4,6-Trichloropyrimidin-5-ol

HRID 334111Notes

Reaction equation

HRID 334111 reaction equation
[Cl:1][C:2]1[N:7]=[C:6]([Cl:8])[C:5]([O:9]C)=[C:4]([Cl:11])[N:3]=1.B(Br)(Br)Br>C(Cl)Cl.CO.O>[Cl:1][C:2]1[N:7]=[C:6]([Cl:8])[C:5]([OH:9])=[C:4]([Cl:11])[N:3]=1

Participants

6

Reactant 2

HCID 25134Boron tribromideHCID 202711362,4,6-Trichloro-5-methoxypyrimidine

Product 1

HCID 866673322,4,6-Trichloropyrimidin-5-olYield 71%

Reagents, catalysts & solvents 3

HCID 887MethanolSolventHCID 962WaterSolventHCID 6344DichloromethaneSolvent

Procedure

Under an atmosphere of nitrogen a solution of 2,4,6-trichloro-5-methoxy-pyrimidine (4.0 g, 18.7 mmol) in DCM (200 mL) was cooled to 0° C. and treated with boron tribromide (neat, 6.6 mL, 65 mmol) dropwise. After stirring for 18 hours at room temperature LCMS analysis indicated complete reaction. The reaction mixture was cooled and diluted with methanol (25 mL, CARE, EXOTHERM!) and the reaction mixture diluted with water (200 mL). The aqueous layer was washed with DCM and the combined organic extracts dried (Na2SO4) filtered and concentrated in vacuo to give 2,4,6-trichloro-5-hydroxy-pyrimidine as a pale tan solid (2.55 g, 71%). 13C NMR (DMSO-d6): 149.23 (C), 145.25 (C), 145.08 (C). LCMS: RT=2.65/2.77 [M−H]−=197/199.

Workup

  1. customreaction
  2. temperatureThe reaction mixture was cooled
  3. washThe aqueous layer was washed with DCM
  4. dry with materialthe combined organic extracts dried (Na2SO4)
  5. filtrationfiltered
  6. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-e20c18e7ce4341dbb38a5e6c4cd57322
Source dataset
uspto-grants-2014_11
Patent number
US08883799B2

Reaction notes

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