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

Participants

Reaction Conditions

Reaction Steps

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)+.

Provenance & Evidence