Fun with Lego (molecules)

(Nanowerk News) A great childhood pleasure is playing with LegosĀ® and marveling at the variety of structures you can create from a small number of basic elements. Such control and variety of superstructures is a goal of polymer chemists, but it is hard to regulate their specific size and how the pieces fit together.
This week in ACS Central Science ("Toward Controlled Hierarchical Heterogeneities in Giant Molecules with Precisely Arranged Nano Building Blocks"), researchers report a simple system to make different nano-architectures with precision.
building-block molecules
Depending on the relative amounts of different building-block molecules, it is possible to create different sandwich and wheel topologies (shown above in micrographs and below as models). (© American Chemical Society) (click on image to enlarge)
Using a variety of highly efficient chemical transformations and other techniques to ensure high yields and purity, Stephen Z. D. Cheng, Yiwen Li, Wen-Bin Zhang and coworkers designed systems to create giant molecules with 'orthogonal' ends, meaning that they only fit together with a specific partner just like LegosĀ®.
Depending on the relative amounts of different building-block molecules, these molecules come together in different superstructures -- ranging from cubes to wheels and sandwiches.
Eventually, they could be employed in device-creation, where it is crucial to have precise control over the positions of the components.
Source: American Chemical Society