Crystal Structures of the Lithium Cryptates of Two Macrobicyclic Ligands Containing Pyridine, Bipyridine, and Biisoquinoline Units

Abstract

The crystal structures of the LiBr complexes of two macrobicyclic ligands, [py.py.bpy]1 and [py.biqi.biqi] 2, have been determined. They confirm the cryptate nature of these species. In 3, the Li⁺ cation is bound in the shallow cavity of a ligand of flattened shape, whereas in 4, it is buried inside the macrobicycle and surrounded by its three bridges.