2-Bromopyridine → 2-Phenylacetophenone

HRID 1650721Notes

Reaction equation

HRID 1650721 reaction equation
N1[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[CH3:7].Br[C:9]1[CH:14]=[CH:13][CH:12]=[CH:11]N=1.[Li+].[CH3:16][CH2:17]C[CH2-].[CH3:20][O:21][N-]C>CCOCC.CCCCCC>[C:2]1([C:20]([CH2:9][C:14]2[CH:17]=[CH:16][CH:11]=[CH:12][CH:13]=2)=[O:21])[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

7

Reactant 4

HCID 79732-BromopyridineHCID 79752-MethylpyridineHCID 61028n-Butyl lithiumHCID 53630747Methoxy-methyl amide

Product 1

HCID 99482-Phenylacetophenone

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolvent2×HCID 8058HexaneSolvent

Conditions

Temperature
-78 °C

Procedure

A solution of 1.2 equivalents of the appropriate picoline or bromopyridine in ether at -78° C. under nitrogen was treated with 1 equivalent of N-butyllithium in hexane and then stirred one hour without cooling to generate the anion. The reaction was again cooled to -78° C. and an ether solution containing 1 equivalent of the appropriate N-methoxy-N-methylamide from procedure 1 was added dropwise. After the addition was complete the reaction was allowed to come to room temperature and stirred for 3 hr. Any excess butyllithium was quenched with isopropyl alcohol at -78° C., water was added at room temperature, and the ether was stripped off. The product was treated with excess 0.25M NaOH, extracted into methylene chloride, and stripped.

Workup

  1. temperaturewithout cooling
  2. additionwas added dropwise
  3. additionAfter the addition
  4. customto come to room temperature
  5. stirringstirred for 3 hr
  6. customAny excess butyllithium was quenched with isopropyl alcohol at -78° C.
  7. additionwater was added at room temperature
  8. additionThe product was treated with excess 0.25M NaOH
  9. extractionextracted into methylene chloride

Sources & evidence

ORD record
ord-0ece4cc262e54ed88e1f8936c1168615
Source dataset
uspto-grants-1990_05
Patent number
US04925857

Reaction notes

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