Crystal engineering strategy

Aakeroy, C. B. (1997). Crystal engineering strategies and architectures. Acta. Crystallogr. B53, 569. 

Diamondoid networks represent just one example of the types of architecture that can be generated in a rational manner using the modular self-assembly approach. The remainder of this chapter will focus upon the diversity of simple architectures that are accessible using crystal engineering strategies, many of which have no precedent in minerals yet are afforded via one-pot reactions and commercially available components. 

Gavezzotti, Gavezzotti and Filippini, Desiraju, and Etter ° have described crystal engineering strategies to understand the molecular aggregation processes involved in crystallization and to elucidate the supramolecular motifs in organic crystals. In this context, crystals are viewed as solid-state supermolecules assembled by intermolecular interactions, with the basic approach of establishing a relation between... 

C. B. Aakeroy, Acta Crystallogr. B, 53, 569 (1997). Crystal Engineering Strategies and Architectures. 

In the context of crystal engineering strategies a frequently asked question [30] is given the molecular structure of an organic substance, what is its crystal... 

The existence of polymorphism in crystals can, at one stroke, demolish a well-planned and logically devised strategy to obtain a target supramolecular structure. Instead of treating this phenomenon as a complication or nuisance in crystal engineering strategies, a more positive approach is to view it as an excellent opportimity to study the same chemical substance in different crystalline... 

Some examples of utilization ofHB in crystal engineering strategies are presented in the following. The reader is referred to the entries on crystal engineering and to those on the hydrogen bond for more details. The selection of examples is clearly arbitrary and cannot do justice to the number of scientific groups involved in this booming field of research. 

Aakeroy, C.B. Crystal engineering Strategies and architectures. Acta Crystallogr., Sect. B 1997, 53. 569-586. 

As outlined by Desiraju, crystal engineering strategies rely on the use of supramolecular synthons , or structural units within supermolecules that can be assembled using known synthetic operations , in order to achieve favourable erystal packings. Specifically, regarding organic-based moleeules, the supramolecular synthons can exist in two main types namely, homosynthons and heterosynthons (Scheme l). 

Scheme 1 Common synthons in crystal engineering strategies.

A crystal engineering strategy to restore the N-H- -O tape in diaryl ureas is now discussed. First, there are clear differences between the diaryl ureas highlighted in this chapter (N-aromatic) [23, 25-28] and the dibenzyl ureas (N-CH2-aromatic) [14] reported over a decade ago. The same combination of functional groups, namely urea. 

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