Studies on intramolecular alkylation. VIII. The preparation of fluorene-derived tetracyclic ketones : Intermediates for gibberellin synthesis

Abstract

The 1,2,3,4-tetrahydrofluorene-2-carboxylic acids (7) and (13) were prepared and converted via their diazomethylcarbonyl derivatives (5) and (6) to give 1,2,3,9a-tetrahydro-7-methoxy-2,9a-ethano-fluoren-11-one (3) and its 2-hydroxy derivative(4), respectively.