Acetic Acid → alpha-Methyl-2-pyridineethanol

HRID 1974122Notes

Reaction equation

HRID 1974122 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([C:8](=[O:10])[CH3:9])=[CH:4][CH:3]=1.[N:11]1[CH:16]=[CH:15][CH:14]=[CH:13][C:12]=1[CH3:17].C(O)(=O)C>C1C=CC=CC=1>[N:11]1[CH:6]=[CH:7][CH:2]=[CH:3][C:4]=1[CH2:5][CH:8]([OH:10])[CH3:9].[Br:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]([CH3:9])=[CH:17][C:12]2[CH:13]=[CH:14][CH:15]=[CH:16][N:11]=2)=[CH:4][CH:3]=1

Participants

6

Reactant 3

HCID 176Acetic AcidHCID 7466p-BromoacetophenoneHCID 79752-Methylpyridine

Product 2

HCID 578865alpha-Methyl-2-pyridineethanolYield 63%HCID 541806622-[2-(4-Bromophenyl)prop-1-en-1-yl]pyridineYield 26%

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Procedure

2-p-Bromophenyl)- 1-(2-pyridyl-2-propanol is prepared from p-bromoacetophenone and 2-picoline according to the method of Villani, et al., J. Med. Chem., 13, 359 (1970) in 63% yield. This alcohol (129.1 g.) is dehydrated by heating in 1150 ml. of acetic acid-12N hydrochloric acid (3:1) at reflux temperature for 4 hr. The mixture is evaporated in vacuo, made basic with concetrated ammonium hydroxide, and extracted with ethyl acetate. The ethyl acetate extract is washed with water and brine, dried over sodium sulfate, and evaporated to give a dark brown oil. A solution of the oil in benzene is passed through a columm of silica gel. Evaporation of the eluate gave 46.4 g. (26% yield) of crystalline 2-(p-bromophenyl)-1-(2-pyridyl)propene, m.p. 71.5°-73.5° C. (corr.).

Workup

  1. temperatureby heating in 1150 ml
  2. customThe mixture is evaporated in vacuo
  3. extractionextracted with ethyl acetate
  4. extractionThe ethyl acetate extract
  5. washis washed with water and brine
  6. dry with materialdried over sodium sulfate
  7. customevaporated
  8. customto give a dark brown oil
  9. customEvaporation of the eluate
  10. customgave 46.4 g

Sources & evidence

ORD record
ord-628154c6133143d3b18e28a29e986258
Source dataset
uspto-grants-1976_12
Patent number
US04000143

Reaction notes

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