1,2-Dibromoethane → 2-Methyloct-1-en-6-yn-3-ol

HRID 65907

Reaction equation

HRID 65907 reaction equation
C(Br)CBr.Br[C:6]([CH3:8])=[CH2:7].[CH:9](=[O:15])[CH2:10][CH2:11][C:12]#[C:13][CH3:14].[Cl-].[NH4+]>O1CCCC1>[CH3:8][C:6]([CH:9]([OH:15])[CH2:10][CH2:11][C:12]#[C:13][CH3:14])=[CH2:7]

Participants

6

Reactant 4

HCID 78391,2-DibromoethaneHCID 112022-BromopropeneHCID 25517Ammonium ChlorideHCID 10975410Hex-4-ynal2×

Product 1

HCID 126539292-Methyloct-1-en-6-yn-3-olYield 85%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

Magnesium (14.4g, 0.6g atom) was dried in a 250ml flask fitted with reflux condenser, mechanical stirrer and addition funnel. After initiation of reaction under dry N2 with about one ml ethylene dibromide in 70ml tetrahydrofuran, 36.0g (0.30 mole) 2-bromopropene was added dropwise at such a rate as to maintain reflux without external heating. The Grignard solution was then stirred until it cooled to room temperature (30 minutes-1 hour). It was then cooled further to -15° in ice-salt, and the total crude 4-hexynal from part (c) above was added dropwise over 15 minutes. The reaction mixture was stirred for 2 hours at room temperature, saturated ammonium chloride solution was added and the product was extracted with ether. There was obtained 23.50g of 2-methyloct-1-en-6-yn-3-ol (85%, based on 4-methyl hexynoate) as a pale yellow oil.

Workup

  1. dry with materialMagnesium (14.4g, 0.6g atom) was dried in a 250ml flask
  2. customfitted
  3. temperaturewith reflux
  4. additioncondenser, mechanical stirrer and addition funnel
  5. additionwas added dropwise at such a rate as
  6. temperatureto maintain
  7. temperaturereflux without external heating
  8. stirringThe reaction mixture was stirred for 2 hours at room temperature
  9. extractionthe product was extracted with ether

Sources & evidence

ORD record
ord-b24878b02837494690d9a7b9ee9fa0c1
Source dataset
uspto-grants-1978_12
Patent number
US04129599

Linked notes

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