反应详情

To a solution of BF3.OEt2 (1.30 g, 9.2 mmol) and butyraldehyde (0.40 g, 5.5 mmol) in DCM (5 ml) under N2 at −78° was added a solution of 1,2-bis trimethylsilyloxycyclobutene (1.4 g, 6.1 mmol) in DCM (3 ml) maintaining a temperature of less than −70°. After 2 h at −78° the solution was poured into saturated NaHCO3, extracted into EtOAc, washed (brine), dried (MgSO4) and the solution concentrated in vacuo to yield a clear liquid. To this liquid was added TFA (20 ml) and the solution heated at reflux for 24 h.

1. temperaturemaintaining a temperature of less than −70°
2. extractionextracted into EtOAc
3. washwashed (brine)
4. dry with materialdried (MgSO4)
5. concentrationthe solution concentrated in vacuo
6. customto yield a clear liquid
7. temperaturethe solution heated
8. temperatureat reflux for 24 h.