Sodium ethoxide → 2-(Bromomethyl)-5-fluoro-2,3-dihydrobenzofuran

HRID 1730204Notes

Reaction equation

HRID 1730204 reaction equation
[O-]CC.[Na+].[Na].Br[CH:7]([CH2:20][Br:21])[CH2:8][C:9]1[CH:10]=[C:11]([F:19])[CH:12]=[CH:13][C:14]=1[O:15]C(=O)C>C(O)C>[Br:21][CH2:20][CH:7]1[CH2:8][C:9]2[CH:10]=[C:11]([F:19])[CH:12]=[CH:13][C:14]=2[O:15]1

Participants

5

Reactant 3

HCID 2723922Sodium ethoxideHCID 5360545SodiumHCID 21443001HCID 21443001, compound

Product 1

HCID 983242-(Bromomethyl)-5-fluoro-2,3-dihydrobenzofuran

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent2×

Procedure

A sodium ethoxide solution, prepared in the conventional manner starting from 15.2 parts of sodium in 100 parts of ethanol, is added dropwise to a mixture of 231 parts of 3-(2,3-dibromopropyl)-4-acetoxy-fluorobenzene in 800 parts of ethanol (exothermic reaction: temperature rises to 50° C.). Upon completion, stirring is continued for 2 hours at reflux temperature. The reaction mixture is cooled to room temperature, filtered from some insoluble matter and the filtrate is evaporated. The residue is divided between water and ether. The aqueous layer is separated and extracted once more with ether. The combined ethereal phases are dried over calcium chloride, filtered and evaporated. The oily residue is distilled in vacuo, yielding 102 parts of 2-bromomethyl-2,3-dihydro-5-fluorobenzofuran; bp. 100°-105° C. at 1.5 mm. pressure.

Workup

  1. temperatureat reflux temperature
  2. filtrationfiltered from some insoluble matter
  3. customthe filtrate is evaporated
  4. customThe aqueous layer is separated
  5. extractionextracted once more with ether
  6. dry with materialThe combined ethereal phases are dried over calcium chloride
  7. filtrationfiltered
  8. customevaporated
  9. distillationThe oily residue is distilled in vacuo

Sources & evidence

ORD record
ord-f50b8bdf6e0f4fbc8ed526e2750ae2e8
Source dataset
uspto-grants-1976_11
Patent number
US03991202

Reaction notes

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