Formation of chiral solids via a molecular building block approach

The application of principals of molecular recognition to the design of org anic and inorganic solids is leading to remarkable progress in the preparat ion of porous and chiral materials. A new area of supramolecular complexes is metallamacrocycles, large molecules that are sewn together using metal l inkages. Metallacrowns ns are a member of this class of inorganic complexes . In this article we develop a strategy for the preparation of solids that are chiral using metallacrowns as the centerpiece. First, we introduce the available structure types for these molecules and then proceed to describe some of the physical properties associated with this unique molecular assem bly. We demonstrate that chirality can be incorporated simply and inexpensi vely into these molecules and then we show how the metallacrowns can be use d as building blocks to make layered solids with chiral channels. Finally, we assess more general strategies that could be used to engineer truly poro us and chiral materials with high metal densities. (C) 2000 Academic Press.