Supramolecular synthetic strategies

Brammer, L., Swearingen, J. K., Bruton, E. A., Sherwood, P., Hydrogen bonding and perhalometallate ions a supramolecular synthetic strategy for new inorganic materials. Proc. Nat. Acad. Sci. USA 2002, 99, 4956-4961. 

Most of the supramolecular synthetic strategies rely upon the preprogramming of synthons, in order to allow a directed-assembly approach. In fact, the electronic coupling, the dehnition of cavities and channels for ion and/or substrate diffusion, the peculiar catalytic or photochemically active sites environment, among other aspects, can be dehned by the structure and chemical nature of the building blocks. 

This section will provide some practical approaches to the design of binary and ternary supermolecules and co-crystals by outlining supramolecular synthetic strategies based upon modular hydrogen-bond driven approaches. 

Supramolecular synthetic strategies provide a bottom-up approach to this challenging field. In particular, the metal-driven assembly is an efficient, highly convergent synthetic strategy that is used, often in combination with other non-covalent interactions and/or with more conventional covalent procedures, for constructing robust and shape-persistent assemblies of nanoscopic dimensions in which the number, position, relative orientation and distance of the chromophores are well defined [39-41]. 

It has been observed that with N -phenyl urethanes the conformation of the alkyl link between the diacetylene and urethanes can have an effect on the polymerization. When the alkyl group contained an even number of carbon atoms (four or six) the polymerization occurred as anticipated but failed with an odd number of carbon atoms (five). Although the association of all of these urethanes was the same, the low energy molecular conformations of this latter compound do not allow for close contact of the 1,4 atoms of adjacent diacetylenes shown in Figure 1. This observation demonstrates the importance to consider both intermolecular and intramolecular interactions in the design of a supramolecular synthetic strategy. 

On the basis of the extensive structural data obtained from the CSD, it is obvious that in order to bring together two different discrete neutral molecular species into the same crystalline lattice, there should be some thermodynamically based reason (originating from a heteromeric molecular-recognition event) for the subsequent solid-state assembly. Although sfiay structures that cannot readily be explained within such a context will appear from time to time, there is no doubt that the overall structural trends, patterns of behavior, and reproducible motifs can be developed into reliable and versatile supramolecular synthetic strategies. 

When supramolecular chemistry emerged at the forefront of science, it embodied colloid chemistry as one of its facets. A semantic boundary exists between supramolecular chemistry and colloids, as the former involves design logistics a priori in addition to preselected synthetic strategies. The simplest kind of colloidal... 

In conclusion, considering all the attractive features of oiganometallic dendritic macromolecules, the continuous development of synthetic strategies for the construction of new families of such dendrimers, which will play a key role in the future research of supramolecular chemistry and material science, appears to be very promising. 

The synthesis of interlocked molecules has become commonplace over the past 25 years with the gradual development of a number of highly facile template methods for their construction. What were once laboratory curiosities have now taken a prominent place in the broad field of supramolecular chemistry, especially regarding their uses and further potential as molecular switches and machines [1], We present here an overview of the main synthetic approaches to these molecules, with a focus on methods in which macrocyclization reactions result in interlocked products. The analysis is by no means meant to be comprehensive or exhaustive in detail, but rather to convey the variety and utility of the selected synthetic strategies in generating abiotic rotaxane and catenane superstructures. 

In this synthetic strategy, supramolecular interactions are used to construct the catalyst backbone. The approach can be used for a wide variety of catalysts, and mechanistic effects include catalytic supramolecular assemblies, self-assembly, metal-mediated catalysis and organocatalysis, and chiral induction. 

Although supramolecular synthons have been used to construct networks, it is important to note that such structural units may also be used to construct functional solids based on finite assemblies of molecules. That supramolecular synthons may be used to construct such solids stems from the fact that the synthetic strategy to... 

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