Hexamethylphosphoramide → 2-(4-Bromo-2-methylphenyl)-3-pyridin-3-ylpropanenitrile

HRID 2194920Notes

Reaction equation

HRID 2194920 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([CH2:8][C:9]#[N:10])=[C:4]([CH3:11])[CH:3]=1.CN(C)P(N(C)C)(N(C)C)=O.C[Si](C)(C)[N-][Si](C)(C)C.[Li+].Br.Br[CH2:35][C:36]1[CH:37]=[N:38][CH:39]=[CH:40][CH:41]=1>C1COCC1.C([O-])(O)=O.[Na+]>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([CH:8]([CH2:35][C:36]2[CH:37]=[N:38][CH:39]=[CH:40][CH:41]=2)[C:9]#[N:10])=[C:4]([CH3:11])[CH:3]=1

Participants

7

Conditions

Temperature
-78 °C

Procedure

To a solution (4-bromo-2-methylphenyl)acetonitrile (III.1; 1 eq.) in THF (0.18M) and hexamethylphosphoramide (HMPA; 3.3 eq.) at −78° C. was added lithium hexamethyldisilazide (LiHMDS; 1.9 eq.). The reaction mixture was stirred 30 min at −78° C. To the resulting solution was cannulated a suspension of 3-(bromomethyl)pyridine hydrobromide salt (0.8 eq.) in THF (0.1M). The final mixture was allowed to warm slowly to 0° C., stirred 2 h, warm to room temperature then stirred for an extra 2 h. The resulting mixture was poured in saturated aqueous NaHCO3 and finally extracted with EtOAc. The organic extract was washed with water, brine, dried over Na2SO4 filtered and concentrated. Purification by column chromatography on silica gel (Combi-Flash by ISCO), eluting with Hex/EtOAc (0 to 60% in 30 min) afforded the desired compound as a colorless oil.

Workup

  1. temperatureto warm slowly to 0° C.
  2. stirringstirred 2 h
  3. temperaturewarm to room temperature
  4. stirringthen stirred for an extra 2 h
  5. extractionfinally extracted with EtOAc
  6. extractionThe organic extract
  7. washwas washed with water, brine
  8. dry with materialdried over Na2SO4
  9. filtrationfiltered
  10. concentrationconcentrated
  11. customPurification by column chromatography on silica gel (Combi-Flash by ISCO)
  12. washeluting with Hex/EtOAc (0 to 60% in 30 min)

Sources & evidence

ORD record
ord-c546dba1529c417484ab727b356a7372
Source dataset
uspto-grants-2012_12
Patent number
US08334308B2

Reaction notes

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