Propargyl alcohol → Prop-2-ynyl 3-oxopentanoate

HRID 1471328Notes

Reaction equation

HRID 1471328 reaction equation
[O:1]=[C:2]([CH2:8][CH3:9])[CH2:3][C:4]([O:6][CH3:7])=[O:5].[CH2:10](O)[C:11]#C>C1(C)C=CC=CC=1.II>[O:1]=[C:2]([CH2:8][CH3:9])[CH2:3][C:4]([O:6][CH2:7][C:10]#[CH:11])=[O:5]

Participants

5

Reactant 2

HCID 7859Propargyl alcoholHCID 121699Methyl 3-oxovalerate

Product 1

HCID 58512883Prop-2-ynyl 3-oxopentanoateYield 43.4%

Reagents, catalysts & solvents 2

HCID 807IodineCatalystHCID 1140TolueneSolvent

Conditions

Temperature
115 °C

Procedure

To a solution of methyl 3-ketopentanoate (3) (822 mg, 6.00 mmol) and 2-propynol (686 mg, 12.0 mmol) in toluene (7 mL) is added I2 (46 mg, 0.18 mmol). The mixture is stirred at 115° C. for 6 h, then cooled to room temperature, and extracted with ethyl acetate (100 mL). The extract is washed (brine) and dried. After solvent removal at reduced pressure, the residue is distilled (125-130° C., 2 mm) to give 401 mg (43%) of 4 as a colorless liquid. IR 3345, 2856, 1715, 1456 cm−1; 1H NMR (CDCl3) δ 1.10 (t, J=7.5 Hz, 3H, CH2CH3), 2.52 (t, J=2.4 Hz, 1H, CH≡CCH2), 2.58 (q, J=7.5 Hz, 2H, CH2CH3) 3.51 (s, 2H, CH2), 4.74 (d, J=2.4 Hz, 2H, CH≡CCH2).

Workup

  1. temperaturecooled to room temperature
  2. extractionextracted with ethyl acetate (100 mL)
  3. washThe extract is washed (brine)
  4. customdried
  5. customAfter solvent removal at reduced pressure
  6. distillationthe residue is distilled (125-130° C., 2 mm)

Sources & evidence

ORD record
ord-bcae3fa0d79f490eb7d2bc8b3b520f5b
Source dataset
uspto-grants-2015_04
Patent number
US09012217B2

Reaction notes

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