Towards New Materials Via Self-Assembly Cage Compounds, Coordination Polymers, Discs, and Screws

Abstract

Attempts to directly double-deprotonate malonic esters to the corresponding dianions, then quenching the reaction with oxalyl chloride, led finally to the one-pot synthesis of tetranu-clear chelate complexes, formed by self-assembly. Their structure unequivocally is established by X-ray analyses. Highlight among these species is an overall neutral mixed-valence, tetranuclear iron chelate cluster. The alkali cation captured within the cage compensates for the excess negative charge. On the basis of these results, the predictable nature of coordination chemistry has been applied successfully for the specific generation of the metalla-topomers of the well known organic-based coronates, {2}-cryptates, and {3}-cryptates. Consequently, tetrazolylenoles, originally prepared for totally different purposes, offered an additional property and were used as chelating ligands for the generation of one-, two-, and three-dimensional coordination polymers, characterised by X-ray structure analyses.

Key Words:

• Supramolecular chemistry
• Self-assembly
• Coordination polymers
• Iron