HCID 367206, compound → 3-(2-Bromophenyl)prop-2-en-1-ol

HRID 485721Notes

Reaction equation

HRID 485721 reaction equation
[Br:1][C:2]1[CH:14]=[CH:13][CH:12]=[CH:11][C:3]=1[CH:4]=[CH:5][C:6](OCC)=[O:7].[H-].C([Al+]CC(C)C)C(C)C>C1(C)C=CC=CC=1>[Br:1][C:2]1[CH:14]=[CH:13][CH:12]=[CH:11][C:3]=1[CH:4]=[CH:5][CH2:6][OH:7]

Participants

4

Reactant 2

HCID 367206HCID 367206, compoundHCID 21225700Diisobutylaluminumhydride

Product 1

HCID 534016113-(2-Bromophenyl)prop-2-en-1-olYield 61%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent2×

Procedure

Ethyl o-bromocinnamate (66.3 g; 260 mM) was dissolved in 750 ml of anhydrous toluene under nitrogen in a three-neck round bottom flask equipped with addition funnel and condensor. A toluene solution of diisobutylaluminum hydride (520 mM; 1.53 M) was transferred via canula to the addition funnel and then added dropwise to the reaction mixture, which had been chilled to -78°. After the addition was completed the reaction was warmed to ambient temperature over a 1.5 hour period and quenched by the dropwise addition of 50 ml of water. Some cooling was required. The resulting emulsion was added to 640 ml of 2N aqueous hydrochloric acid. After partitioning, the slightly acidic (pH 5) aqueous layer was extracted twice with ether. The combined organic fractions were dried (MgSO4), filtered (fritted funnel), and evaporated to afford an oil. The oil was chromatographed in two portions on the Waters Prep 500 equipped with two cartridges eluting with a total of two gallons of 35% ethyl acetate in hexane. This produced 33.8 g (61% yield) of o-bromocinnamylalcohol. NMR (CDCl3): δ6.8-7.8 (m; 5H); 6.0-6.6 (AB; 1H); 4.2-4.4 (brd.; 2H); 2-2.6 (brs; 1H).

Workup

  1. customequipped with addition funnel
  2. additionadded dropwise to the reaction mixture, which
  3. temperaturehad been chilled to -78°
  4. additionAfter the addition
  5. customquenched by the dropwise addition of 50 ml of water
  6. additionThe resulting emulsion was added to 640 ml of 2N aqueous hydrochloric acid
  7. customAfter partitioning
  8. extractionthe slightly acidic (pH 5) aqueous layer was extracted twice with ether
  9. dry with materialThe combined organic fractions were dried (MgSO4)
  10. filtrationfiltered (fritted funnel)
  11. customevaporated
  12. customto afford an oil
  13. customThe oil was chromatographed in two portions on the Waters Prep 500
  14. customequipped with two cartridges
  15. washeluting with a total of two gallons of 35% ethyl acetate in hexane

Sources & evidence

ORD record
ord-d680bc45582041d8964ad05f9df9b6b8
Source dataset
uspto-grants-1985_08
Patent number
US04537903

Reaction notes

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