反应详情

2.10 mg of Lawesson reagent were added to a solution of 400 mg of the product of Example 3 in 20 ml of toluene and the mixture was refluxed for 90 minutes. The mixture was poured into 100 ml of water and extraction was carried out with ethyl acetate. Th extracts were washed with water, dried, filtered and evaporated to dryness to obtain 0.6 g of the expected product which was chromatographed on silica (eluant: methylene chloride-acetone (98-2)) to collect 0.42 g of the desired product melting at 158° C.

1. temperaturethe mixture was refluxed for 90 minutes
2. washTh extracts were washed with water
3. customdried
4. filtrationfiltered
5. customevaporated to dryness