Phosphorus oxychloride → 2-Chloro-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)imidazo[1,2-a]pyridine

HRID 414919Notes

Reaction equation

HRID 414919 reaction equation
Br.C(O[C:5](=O)[CH2:6][N:7]1[CH:12]=[C:11]([B:13]2[O:17][C:16]([CH3:19])([CH3:18])[C:15]([CH3:21])([CH3:20])[O:14]2)[CH:10]=[CH:9][C:8]1=[NH:22])C.O=P(Cl)(Cl)[Cl:26]>>[Cl:26][C:5]1[N:22]=[C:8]2[CH:9]=[CH:10][C:11]([B:13]3[O:17][C:16]([CH3:19])([CH3:18])[C:15]([CH3:21])([CH3:20])[O:14]3)=[CH:12][N:7]2[CH:6]=1

Participants

3

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 86761542Ethyl [2-imino-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2H-pyridin-1-yl]acetate hydrobromide

Product 1

HCID 442323732-Chloro-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)imidazo[1,2-a]pyridine

Conditions

Temperature
105 °C

Procedure

8.78 g of ethyl[2-imino-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyridin-1-yl]acetate hydrobromide in 20 ml of POCl3 are placed in a round-bottomed flask. The reaction mixture is heated at 105° C. for 16 h, cooled to ambient temperature and concentrated under reduced pressure. The residue is taken up between dichloromethane and water at 0° C., and a 30% aqueous solution of NH4OH is added until a basic pH is obtained. The organic phase is separated, dried over magnesium sulphate and concentrated under reduced pressure. 4.3 g of compound are obtained.

Workup

  1. temperaturecooled to ambient temperature
  2. concentrationconcentrated under reduced pressure
  3. customis taken up between dichloromethane and water at 0° C.
  4. additiona 30% aqueous solution of NH4OH is added until a basic pH
  5. customis obtained
  6. customThe organic phase is separated
  7. dry with materialdried over magnesium sulphate
  8. concentrationconcentrated under reduced pressure

Sources & evidence

ORD record
ord-548706e46c1f4ed79f3d42a458df1076
Source dataset
uspto-grants-2012_01
Patent number
US08088765B2

Reaction notes

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