Synthesis of optically active sesquiterpene alkaloids, patchoulipyridine and related compounds, was accomplished by application of a method for constructing cycloalkenopyridines by thermal rearrangement of O-2-butenyloximes.
A Pd-catalyzed asymmetric alkene 1,2-dioxygenation reaction is described. The diastereoselectivity of the reaction is controlled by tethering a chiral oxime ether directing group to the alkene substrate. The best selectivities are obtained with 8-substituted menthone-derived oxime ether auxiliaries.