The thermal and anionic rearrangements of trans-1-vinylcyclotridec-3-en-1-01 compounds substituted in the a and@ vinyl positions have been examined to determine whether the substituents can be used to control the periselectivity. For the anionic rearrangements, trimethylsilyl groups were found to be unsuitable, and terminal vinyl methyl or isopropyl groups did not provide a useful selectivity. Under thermal conditions, either a terminal ...