Synthesis of 5′-(3,3-Dimethylallyl)-4′-Methoxyethoxymethyl Resacetophenone and Improved Preparation of Broussochalcones A and B

Abstract

5′-(3,3-Dimethylallyl)-4′-methoxyethoxymethyl resacetophenone has been synthesized in 77% yield by para sigmatropic rearrangement of 2′-(3,3-dimethylallyl)-4′-methoxyethoxymethyl resacetophenone. Using this newly synthesized prenyl resacetophenone precursor, the yields of preparation of the naturally occurring broussochalcones A and B have been increased by a factor of 30 and 5, respectively.

Key Words:

• Prenyl chalcones
• Prenyl resacetophenone
• Preparation
• Sigmatropic rearrangement
• Broussochalcone A
• Broussochalcone B