反应详情

11 mL of trifluoroacetic acid was added under ice cooling to a 40 mL chloroform solution of 3.85 g of the compound obtained in step 3-4, and the reaction mixture was stirred for 2 hours at room temperature. The solvent was then distilled off under reduced pressure to obtain 8.02 g of residue (pale yellow oily substance). This compound was used in the following reaction without being purified.

1. distillationThe solvent was then distilled off under reduced pressure