Potassium tert-butoxide → 5-(Benzyloxy)-1-methylene-1,2-dihydrocyclobutabenzene

HRID 404321Notes

Reaction equation

HRID 404321 reaction equation
[CH2:1]([O:8][C:9]1[CH:10]=[CH:11][C:12]2[CH2:16][C:15](=O)[C:13]=2[CH:14]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[CH3:18]C([O-])(C)C.[K+]>C1COCC1.[Br-].C[P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1>[CH2:1]([O:8][C:9]1[CH:10]=[CH:11][C:12]2[CH2:16][C:15](=[CH2:18])[C:13]=2[CH:14]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

5

Reactant 2

HCID 23665647Potassium tert-butoxideHCID 583803075-(Benzyloxy)cyclobutabenzen-1(2H)-one

Product 1

HCID 583800515-(Benzyloxy)-1-methylene-1,2-dihydrocyclobutabenzene

Reagents, catalysts & solvents 2

HCID 74505Methyltriphenyliphosphonium bromideCatalystHCID 8028TetrahydrofuranSolvent

Conditions

Temperature
0 °C

Procedure

H7.2 (13.0 g, 58.0 mmol) was dissolved in 300 mL THF. The resulting solution was cooled to 0° C. in an ice-water bath. Methyltriphenylphosphonium bromide (24.8 g, 69.6 mmol) (commercially available from Sigma-Aldrich, St. Louis, Mo., USA) was added and some yellow solid appeared. Potassium 2-methylpropan-2-olate (69.6 mL, 69.6 mmol) (commercially available from Sigma-Aldrich, St. Louis, Mo., USA) was then added dropwise over an hour. The reaction was stirred at 0° C. for another hour and then quenched by addition of 200 mL saturated NaHCO3. The THF solvent was evaporated by vacuum and the residue was extracted twice with 200 mL EtOAc. The combined organic layers were washed with brine, dried over MgSO4, filtered, and then concentrated in the presence of silica gel. The residue was purified by column chromatography with 10% EtOAc/hexane to afford H7.3 (4.1 g, 31.8%). MS ESI (pos.) m/e: 223.1 (M+H)+.

Workup

  1. addition, USA) was added
  2. addition, USA) was then added dropwise over an hour
  3. customquenched by addition of 200 mL saturated NaHCO3
  4. customThe THF solvent was evaporated by vacuum
  5. extractionthe residue was extracted twice with 200 mL EtOAc
  6. washThe combined organic layers were washed with brine
  7. dry with materialdried over MgSO4
  8. filtrationfiltered
  9. concentrationconcentrated in the presence of silica gel
  10. customThe residue was purified by column chromatography with 10% EtOAc/hexane
  11. customto afford H7.3 (4.1 g, 31.8%)

Sources & evidence

ORD record
ord-0d6cfef27d5341abba72c1be3378f143
Source dataset
uspto-grants-2014_06
Patent number
US08748462B2

Reaction notes

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