Water → Benzene, 1,2,5-trichloro-3-methoxy-

HRID 274830Notes

Reaction equation

HRID 274830 reaction equation
[H-].[Al+3].[Li+].[H-].[H-].[H-].[Cl:7][C:8]1[C:16]([Cl:17])=[CH:15][C:14]([Cl:18])=[CH:13][C:9]=1[C:10](O)=[O:11].O.[OH-].[Na+]>C(OCC)C>[Cl:7][C:8]1[C:16]([Cl:17])=[CH:15][C:14]([Cl:18])=[CH:13][C:9]=1[CH2:10][OH:11]

Participants

6

Reactant 4

HCID 962Water2×HCID 14798Sodium HydroxideHCID 661212,3,5-Trichlorobenzoic acidHCID 21226445Aluminium lithium hydride

Product 1

HCID 41018Benzene, 1,2,5-trichloro-3-methoxy-Yield 72.8%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent2×

Procedure

A suspension of 5.5 grams (0.144 mole) of lithium aluminum hydride in 300 mL of diethyl ether was stirred, and 25.0 grams (0.111 mole) of 2,3,5-trichlorobenzoic acid in 200 mL of diethyl ether was added dropwise at a rate which maintained a gentle reflux. The complete addition required about 75 minutes. Upon completion of addition, the reaction was mixture heated at reflux for 4.5 hours. After this time the reaction mixture was stirred for about 16 hours, during which time it was allowed to cool to ambient temperature. The reaction mixture was then cooled to below 10° C., and 6 mL of water was added slowly dropwise. Upon completion of addition, 5 mL of aqueous 20% sodium hydroxide was added dropwise, followed by an additional 12 mL of water added dropwise. The reaction mixture was then stirred for 20 minutes and filtered through diatomaceous earth. The filtrate was concentrated under reduced pressure to a residue. The residue was stirred into water, and the combination was extracted with ethyl acetate. The extracts were combined and washed with three portions of water. The organic layer was dried with sodium sulfate and filtered. The filtrate was concentrated under reduced pressure, yielding 17.1 grams of 2,3,5-trichlorophenylmethanol. The NMR spectrum was consistent with the proposed structure.

Workup

  1. temperaturemaintained a gentle reflux
  2. additionThe complete addition required about 75 minutes
  3. additionUpon completion of addition
  4. temperatureheated
  5. temperatureat reflux for 4.5 hours
  6. stirringAfter this time the reaction mixture was stirred for about 16 hours, during which time it
  7. temperatureThe reaction mixture was then cooled to below 10° C.
  8. additionwas added dropwise
  9. additionadded dropwise
  10. stirringThe reaction mixture was then stirred for 20 minutes
  11. filtrationfiltered through diatomaceous earth
  12. concentrationThe filtrate was concentrated under reduced pressure to a residue
  13. stirringThe residue was stirred into water
  14. extractionthe combination was extracted with ethyl acetate
  15. washwashed with three portions of water
  16. dry with materialThe organic layer was dried with sodium sulfate
  17. filtrationfiltered
  18. concentrationThe filtrate was concentrated under reduced pressure

Sources & evidence

ORD record
ord-f9bf838f8c264b77afad6f7e95206c6e
Source dataset
uspto-grants-1995_02
Patent number
US05391541

Reaction notes

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