Diethyl Ether → Mesityl oxide

HRID 1287708Notes

Reaction equation

HRID 1287708 reaction equation
[Na].[Mg].[C:3]1([CH3:21])[CH:8]=[C:7]([CH3:9])[CH:6]=[C:5](C)[C:4]=1O[C:12]1[C:17]([CH3:18])=[CH:16]C(C)=C[C:13]=1[CH3:20].C([O:24]CC)C>N.C#C>[CH3:21][C:3]([OH:24])([CH:8]=[C:7]([CH3:9])[CH3:6])[C:4]#[CH:5].[O:24]=[C:13]([CH:12]=[C:17]([CH3:16])[CH3:18])[CH3:20]

Participants

8

Reactant 4

HCID 3283Diethyl EtherHCID 5360545SodiumHCID 5462224Magnesium2×HCID 123671641,1'-Oxybis(2,4,6-trimethylbenzene)

Product 2

HCID 8858Mesityl oxideHCID 10678228HCID 10678228, compound

Reagents, catalysts & solvents 2

HCID 222AmmoniaSolventHCID 6326AcetyleneSolvent2×

Procedure

Sodium (30 g.) was dissolved in liquid ammonia (1,500 ml.) and acetylene was passed through the solution until the blue color was discharged. Magnesium turnings (10 g.) were added and the mixture was stirred for 18 hours while acetylene was passed slowly through it. During this period, almost all the magnesium dissolved. A solution of mesityloxide (10.7 g.) in diethyl ether (300 ml.) was cooled to -20° to -40°C. and was added to the reaction mixture over a period of about 5 minutes. The mixture was stirred for 5 hours, the ammonia was evaporated until the temperature of the residue reached -20°C., and the residue was dropped into a solution of sulfuric acid (200 ml.) in water (1,200 ml.) which was maintained at -5° to +15°C. The etheral layer was separated and the aqueous phase was extracted with two portions of diethyl ether (100 ml. each). The combined etheral extracts were washed with a mixture of aqueous saturated sodium bicarbonate solution (20 ml.) and saturated brine (80 ml.), then dried over sodium sulfate and the ether removed by distillation at atmospheric pressure. Distillation of the residue at 25°-34°C./3 mmHg yielded 3,5-dimethylhex-4-en-1-yn-3-ol (57.3 g.) and mesityl oxide (30.0 g.). The conversion of mesityl oxide was thus 72.0% and the yield of product 58.8%.

Workup

  1. waitDuring this period
  2. additionwas added to the reaction mixture over a period of about 5 minutes
  3. customthe ammonia was evaporated until the temperature of the residue
  4. customreached -20°C.
  5. additionthe residue was dropped into a solution of sulfuric acid (200 ml.) in water (1,200 ml.) which
  6. temperaturewas maintained at -5° to +15°C
  7. customThe etheral layer was separated
  8. extractionthe aqueous phase was extracted with two portions of diethyl ether (100 ml
  9. washThe combined etheral extracts were washed with a mixture of aqueous saturated sodium bicarbonate solution (20 ml.) and saturated brine (80 ml.)
  10. dry with materialdried over sodium sulfate
  11. customthe ether removed by distillation at atmospheric pressure
  12. distillationDistillation of the residue at 25°-34°C./3 mmHg

Sources & evidence

ORD record
ord-7645969512fa440d9b0bb25b91c981fe
Source dataset
uspto-grants-1976_10
Patent number
US03985817

Reaction notes

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