Functional supramolecular compounds

An important contribution of macromolecular chemistry to functional supramolecular systems and devices is the limitation of ordering typical for macromolecular compounds and, of course, the long-range interconnectivity between different molecular subunits. 

Single- and multiwalled carbon nanotubes represent attractive components for supramolecular structures. Their rod shape predestines them as guest molecules to be included inside host compounds that are designed like rings or hollow cylinders. From an arrangement with the host wrapped helically around the nano-tube, another type of supramolecular compound arises. The tubes can further serve as scaffold to supramolecular structures that form by a complexation of single tubes or bundles. Several examples of supramolecular patterns have already been discussed in Section 3.5.4.2 on the noncovalent functionalization of nano-tubes. Hence only some other specimens will be presented here. 

Functionalized supramolecular systems based on monolayers of bioactive compounds (macrocyclic ionophoric peptides, crown ethers, nucleoside derivatives) 98MI12. 

Vibrational spectroscopy is clearly a valuable tool for studying the structures and dynamics of supramolecular compounds, including inclusion compounds and macro-cyclic compounds. In addition, resonance Raman mea-rurements were shown to be useful in studying the structure and function of biological molecules (containing macrocyclic moieties). 

Usually the COOH functional groups act both as hydrogen-bond donors and acceptors. The dinuclear tungsten complex [(C5H4COOH)W(CO)3]2, 52 [118], is not a supramolecular compound but it is shown here as an example of hydrogenbonding between carboxylic acid functions and THE. 

Bimetallic platinum complexes are known as unique building blocks and are widely utilized in the coordination-driven self-assembly of functionalized supramolecular metallacycles. A detailed photophysical study of some bimetallic platinum compounds (see formula below) has been carried out, evidencing the role of H bonding with the solvent. 

Functional supramolecular polymeric materials are designed and prepared by incorporation of functional species such as chiral compounds, dyes, and conductive molecules. For these... 

Amino-a-methylene carbonyl compounds have been prepared in up to 92% ee via an aza-Morita-Baylis-Hillman reaction. A-Tosyl imines of, y-unsaturated a-ketoesters have been reacted with acrolein in the presence of two catalysts / -isocupridine (a chiral quinolol containing a DABCO moiety) and a bifunctional BINOL (or a 3 amine-thiourea). NMR and MS evidence supports a self-assembly of the catalysts, giving a multi-functional supramolecular catalyst. 

KD Schierbaum, and W Gopel, "Functional Polymers and Supramolecular Compounds for Chemical Sensors", Conf Proc E-MRS Spnng Meeting 1993, StraBburg (F), and Synth Met 61 (1993)37... 

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