Chemistry of the Podocarpaceae. XLI. The decarbonylation of 12-Methoxypodocarpa-8,11,13-trien-19-oic acid and Abieta-8,11,13-trien-18-oic acid

Abstract

12-Methoxypodocarpa-8,11,13-trien-19-oic acid (1), its acid chloride (3), and its methyl ester (4) undergo a decarbonylation reaction on treatment with phosphoryl chloride. The products have been identified as the octahydrophenanthrene (14), the tetrahydrophenanthrenes (11) and (12), and the phenanthrene (9). A minor product has been tentatively identified as the dimer (16). Decarbonylation of abieta-8,11,13- trien-18-oic acid (28) gives similar products. A pathway leading to the above products is discussed.