In the beginning it was attractive to settle this point through the synthesis of dehydroabietic acid via the introduction of isopropyl group at the C-7 position of the acid I. hIoreorer it appeared quite plausible that introduction of the acetyl group in the octahydrophenanthrene nucleus would take place preferentially at C-7, as this is sterically less hindered than CG. The Friedel-Crafts reaction was first studied with the more accessible material 11, IC and it ...
