反应详情

10 mL of trifluoroacetic acid was added under ice cooling to a 30 mL chloroform solution of 2.09 g of the compound obtained in step 6-2, after which the reaction mixture was stirred for 2 hours at room temperature. The reaction mixture was then concentrated under reduced pressure, which gave 3.42 g of residue (pale yellow oily substance). This compound was used in the following reaction without being purified.

1. concentrationThe reaction mixture was then concentrated under reduced pressure, which