Crystal engineering supramolecular synthons

Keywords Synthesis m Crystal engineering m Supramolecular synthon... 

F. H. Allen, J. P. M. Lommerse, V. J. Hoy J. A. K. Howard, G. R, Desiraju, The halogen—O(nitro) supramolecular synthon in crystal engineering a combined crystallographic database and ab initio molecular orbital study , Acta CrystaUogr, Section B, 1997, 53,1006-1016. 

The identification of the set of interactions that constitute a synthon is, in the end, subjective. In the limit, any possible combination of interactions may be defined as a supramolecular synthon but then there is the risk that the term will be degraded or fall into disuse much like its molecular sibling. Interactions or groups of interactions that are needlessly identified as supramolecular synthons, but are unable subsequently to sustain a predictive role in crystal engineering, will... 

With the recognition that many substances may cocrystallize in a single continuous lattice structure, scientists have more recently initiated intense studies of the mixed molecular crystal systems that have become known as cocrystals [10]. This particular area of solid-state research has led pharmaceutical scientists into the areas of crystal engineering and assembly of appropriate supramolecular synthons, with particular emphasis on understanding the origins of the molecular self-assembly that takes place in the formation of cocrystal systems. 

G.R. Desiraju, Supramolecular synthons in crystal engineering a new organic synthesis, Angew. Chem. Int. Ed. 34 (1995) 2311-2327. 

Hydrogen bonded rings are among the most beautiful and most versatile supramolecular synthons in crystal engineering. A systematic survey of the CSD was undertaken in 1999 to determine the tendency of particular functional groups to form hydrogen bonded ring dimer synthons as opposed to other motifs... 

A considerable amount of fundamental research into understanding the nature and predictability of supramolecular synthons remains to be completed. Indeed, an enhanced database concerning supramolecular synthons in the broad context would also assist our fundamental understanding of solution chemistry and biochemistry. Nevertheless, it is clear that there are a number of applications of crystal engineering that could be realized in the short term. Several of these are summarized below. 

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