Enantiospecific syntheses of pseudopterosin aglycones. Part 1. Synthesis of the putative aglycone of pseudopterosin G-J via an A -> AB -> ABC annulation strategy

The putative aglycone of pseudopterosin G-J and its enantiomer were synthesised enantio specifically from 2,3-dimethoxytoluene and eta (3)-allyl cationic complexes of molybdenum and iron respectively. The A –> AB –> ABC annulation strategy entailed the use of allyl cations or their equivalents for the creation of the three benzylic stereogenic centres. The X-ray structure of tetrahydro naphthalene (-)-41a was determined.