Acetic Acid → 2-Cyclopenten-1-one, 2-ethyl-3-(3-oxo-1-butenyl)-, (E)-

HRID 1759038Notes

Reaction equation

HRID 1759038 reaction equation
[H-].[Na+].[CH2:3]([C:5]1[C:6](=[O:12])[CH2:7][CH2:8][C:9]=1[CH:10]=O)[CH3:4].[C:13]([OH:16])(=O)[CH3:14].O.[CH3:18]OCCOC>C(O)C>[O:16]=[C:13]([CH3:14])/[CH:18]=[CH:10]/[C:9]1[CH2:8][CH2:7][C:6](=[O:12])[C:5]=1[CH2:3][CH3:4]

Participants

7

Reactant 5

HCID 176Acetic AcidHCID 962WaterHCID 80711,2-Dimethoxyethane3×HCID 24758Sodium hydride2×HCID 113095442-Ethyl-3-oxocyclopent-1-ene-1-carbaldehyde

Product 1

HCID 205335842-Cyclopenten-1-one, 2-ethyl-3-(3-oxo-1-butenyl)-, (E)-

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

0.968 (0.023 mole) of a 57% NaH dispersion was transferred into a dry 250 ml flask equipped with a magnetic stirring bar and nitrogen inlet. The NaH was covered with 60 ml of dry DME and a solution of 4.15 g (0.025 mole) of dimethyl (2-oxopropyl) phosphonate in 10 ml of DME was added dropwise. The resulting reaction mixture was stirred for one hour at room temperature. Crude aldehyde 5 supra [from oxidation of 3.4 g (0.025 mole) of the vinyl compound 4] in 15 ml of DME was added dropwise, and the stirring was continued for 2 hours after completion of the addition. The reaction mixture was neutralized with acetic acid and 150 ml of water added. The resulting solution was extracted four times each with 100 ml of ether, and the combined ether extracts back-extracted with 100 ml water and once with 75 ml saturated NaCl. The extracts were dried over MgSO4 and concentrated to yield 3.3 g of crude dione Ib. This material was chromatographed on silicic acid using ethyl acetate-cyclohexane to give a bright yellow liquid: uv (95% ethanol) 293 nm; ir (neat) 1685, 1665, 1640 and 1580 cm-1 (conjugated enone system); ##STR5## and 1.0 (t,3,CH2CH3).

Workup

  1. customequipped with a magnetic stirring bar and nitrogen inlet
  2. customThe resulting reaction mixture
  3. waitthe stirring was continued for 2 hours
  4. additionafter completion of the addition
  5. additionadded
  6. extractionThe resulting solution was extracted four times each with 100 ml of ether
  7. extractionthe combined ether extracts back-extracted with 100 ml water and once with 75 ml saturated NaCl
  8. dry with materialThe extracts were dried over MgSO4
  9. concentrationconcentrated
  10. customto yield 3.3 g of crude dione Ib
  11. customThis material was chromatographed on silicic acid
  12. customto give a bright yellow liquid

Sources & evidence

ORD record
ord-706cd7df6b8f4968a20fab6c88c24f61
Source dataset
uspto-grants-1982_07
Patent number
US04338466

Reaction notes

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