SYNTHESIS OF dl-PENTALENOLACTONES E AND F.

Article abstract of DOI:10.1021/ja00330a044

The methyl esters of ( plus or minus )-pentalenolactone E and F have been synthesized by a route based on the intramolecular insertion of an alpha -acylcarbene into an unactivated C-H bond to effect closure of the key fused delta -lactone ring system. Lactone reduction, deketalization, and selective acetalization of the derived lactol provided as a mixture of epimers.