Amplification of Dynamic Chiral Crown Ether Complexes During Cyclic Acetal Formation

摘要

Dynamic covalent chemistry relates to the study of chemical reactions carried out under thermodynamic control. Labile coordinative bonds associated with certain metal-ligand interactions, ring-opening/ring-closing metathesis reactions, and protocols for the formation of imines and disulfides have all been exploited in the strict self-assembly of catenanes and rotaxanes. A wide range of other functionalities have also been explored in the creation of dynamic combinatorial libraries (DCLs). We describe here the efficient and selective acid-catalyzed formation of a chiral macropolycyclic polyether constituted of multiple [24] crown 8 frameworks, which incorporate either two D- or two Lthreitol residues as bicyclic diacetals, by using dynamic template-directed approaches to amplify the production of the most thermodynamically preferred complex(es).