A method for the stereoselective conversion of 6-alkenyl carbamates into trans-2-alkyl-5- substituted-piperidines utilizing intramolecular amidomercuration as a key step has been developed. As a specific illustration of the method, a synthesis of one of the Hemlock alkaloids,(A)-pseudoconhydrine (trans-5-hydroxy-2-propylpiperidine, 1) was completed. The organomercurial 7a obtained from the intramolecular amidomercuration of 4-[(carbo- ...