Benzyl 3-(2,2-dichloro-3-oxocyclobutyl)propanoate → Benzyl 3-(3-oxocyclobutyl)propanoate

HRID 707670Notes

Reaction equation

HRID 707670 reaction equation
[CH2:1]([O:8][C:9](=[O:19])[CH2:10][CH2:11][CH:12]1[CH2:15][C:14](=[O:16])[C:13]1(Cl)Cl)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1>CC(O)=O.[Zn]>[CH2:1]([O:8][C:9](=[O:19])[CH2:10][CH2:11][CH:12]1[CH2:13][C:14](=[O:16])[CH2:15]1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

4

Reactant 1

HCID 90455769Benzyl 3-(2,2-dichloro-3-oxocyclobutyl)propanoate

Product 1

HCID 67774851Benzyl 3-(3-oxocyclobutyl)propanoateYield 93%

Reagents, catalysts & solvents 2

HCID 23994ZincCatalystHCID 176Acetic AcidSolvent

Conditions

Temperature
80 °C

Procedure

A solution of benzyl 3-(2,2-dichloro-3-oxocyclobutyl)propanoate (8) (11.29 g, 37.49 mmol) in AcOH (100 ml) was treated in small portions with zinc powder (12.26 g, 187.44 mmol, 5 eq.) at RT. After addition, the reaction mixture was stirred at 80° C. for 2 h. LCMS analysis after 2 h shows complete consumption of starting material. The reaction was cooled to RT, diluted with TBME (˜100 ml), filtered and concentrated in vacuo. Heptane (250 ml) was added to remove most of the acetic acid azeotropically. Water (100 ml) was added to the resultant viscous liquid and the mixture was extracted with EtOAc (100 ml×2). The combined organic phase was washed with saturated NaHCO3 (100 ml×1), brine, dried over Na2SO4, filtered and concentrated to yield 8.12 g (93% yield at >95% purity by NMR) of 9 as a clear yellow oil. LCMS analysis on MS 19 shows 92% purity. 1H NMR (500 MHz, CHLOROFORM-d) δ ppm 7.30-7.43 (5 H, m), 5.14 (2 H, s), 3.08-3.21 (2 H, m), 2.64-2.76 (2 H, m), 2.34-2.48 (3 H, m), 1.96 (2 H, q, J=7.62 Hz):

Workup

  1. additionAfter addition
  2. waitLCMS analysis after 2 h shows complete
  3. customconsumption of starting material
  4. temperatureThe reaction was cooled to RT
  5. additiondiluted with TBME (˜100 ml)
  6. filtrationfiltered
  7. concentrationconcentrated in vacuo
  8. additionHeptane (250 ml) was added
  9. customto remove most of the acetic acid azeotropically
  10. additionWater (100 ml) was added to the resultant viscous liquid
  11. extractionthe mixture was extracted with EtOAc (100 ml×2)
  12. washThe combined organic phase was washed with saturated NaHCO3 (100 ml×1), brine
  13. dry with materialdried over Na2SO4
  14. filtrationfiltered
  15. concentrationconcentrated

Sources & evidence

ORD record
ord-5dda651352484b7786034ce3adf8d43f
Source dataset
uspto-grants-2015_11
Patent number
US09175032B2

Reaction notes

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