Selective Oxidations in the Synthesis of Complex Natural -Kauranes and -Beyeranes.

Syntheses of two natural products derived from the -kaurene kaurenoic acid are described for the first time using regio- and diastereoselective oxidations. Palladium- and manganese-mediated oxidations were used to accomplish the syntheses of two -beyerane metabolites. The use of the White-Gormisky-Zhao catalyst Mn(CF-PDP) enabled the first application of a nondirected metal-catalyzed oxidation in an unactivated C-H bond in a total synthesis.