Abstract: The enantiomerizations of several dioxa-(1, 5)-naphthalenophanes (1: n= 14, 15, 16) have been studied by DNMR spectroscopy, and accurate activation parameters have been obtained. Large, negative entropies of activation are observed when n= 14 or 15. In sharp contrast, AS* is very nearly zero when n= 16. Molecular mechanics calculations have been applied to these systems in an effort to obtain some insight into the underlying ...