Supramolecular self-organization

Chemical constitution, steric configuration and, in some cases, details about chain conformation, aggregation, association, and supramolecular self-organization behavior of macromolecular substances can be determined using high-resolution nuclear magnetic resonance (NMR) spectroscopy. This spectroscopic technique is sensitive towards nuclei with a nuclear spin different from zero. 

Makinen R, Ruokolainen J, Ikkala O, De Moel K, ten Brinke G, De Odorico W, Stamm M. Orientation of supramolecular self-organized polymeric nanostructures by oscillatory shear flow. Macromolecules 2000 33 3441-3446. 

Metal NPs were also used as labels to follow aptamer-substrate interactions. The supramolecular self-organization of the aptamer-substrate complexes on surfaces was implemented to develop different configurations of electrical aptasensors.88 The anticocaine aptamer was separated into two fragments (37 and 38) (Fig. 12.24a). The nucleic acid (37) was assembled on a Au electrode, whereas the nucleic acid (38) was... 

Mihai S, Cazacu A, Amal-Herault C, Nasr G, Meffre A, van der Lee A, Barboiu M (2009) Supramolecular self-organization in constitutional hybrid materials. New J Chem 33 2335-2343... 

Molecular mobility and topological chirality of rotaxanes 01ACR465. Rotaxanes. From supramolecular self-organization to molecular devices 00MI21. 

Complex supramolecular structures involving intermo-lecular Sn S, S S secondary bonds and N-H . S hydrogen bonds were observed in organotin derivatives of substituted 5-mercapto-l,3,4-thiadiazoline-2-thione. The simultaneous presence of S-Sb CP secondary bond synthons and CP H-N hydrogen bonds in the solid-state structure of dichlorobis(trimethylenethiour-ea)antimony(III) chloride also leads to an interesting supramolecular self-organization. The cooperation of secondary bonds and Te ti aryl interactions also produces some spectacular supramolecular architectures. 

Casas. J.S. Castiiieiras, A. Haiduc. L Sanchez. A. Sordo. J. Vazquez-Lopez, E.M. Supramolecular self-organization in c /r n<7-poly[(dimethylphosphinothioato) thallium(III)], [TlMe2 S(0)PPh2 ]n, a polymer with secondary interactions between the chain segments. Polyhedron 1994. 13. 1805. 

Fig. 13.21. Self-organization of the tobacco virus. The virus consists of an RNA helix (shown as a single file ) contaming about 7000 nucleotides, which is sufficient genetic material to code the production of 5 — 10 proteins (first level of supramolecular self-organization). The RNA strand interacts very effectively with a certain protein (shown as a drop, which is the second level). The protein molecules associate with the RNA strand forming a kind of necklace, and then the system folds (third level) into a rodUke shape typical for this virus. The rods are able to form a crystal (level four, not shown here), which melts after heating but is restored when cooled down.

Supramolecular self-organization in the solid state has been observed (by X-ray diffraction) for several thallium-oxygen compounds. The secondary Tl - O bonds in these compounds are rather strong and it is debatable whether these should be regarded as electron-pair donor-acceptor bonds or as secondary bonds. 

A clear supramolecular self-organized structure, 131, associated through hydroxo bridges (Sn-O 2.197 A, Sn O 2.255 A), has been determined for triphenyltin hydroxide, PhsSnOH [388] benzyldimethyltin hydroxide has a similar zigzag chain structure (Sn-O 2.17 A, Sn <— O 2.29 A). Cryoscopic measurements show that the compound is dimeric in benzene solution [389],... 

Like carboxylates, numerous organotin derivatives ( esters ) of inorganic and element-organic acids (carbonates, nitrates, phosphates, phosphonates, phosphi-nates and their arsenic analogs, sulfonates, sulfinates, etc.), are characterized by supramolecular self-assembly in solution and/or supramolecular self-organization in solid state. 

The intermolecular contacts and the reciprocal arrangement of molecules in crystals of -C5H5(GO)2CrAs3 are also indicative of supramolecular self-organization. Redrawing of the structure with published atomic coordinates reveals that the molecular tectons form layers with shortest intermolecular As- - As contacts at 3.515 A within the layer, and additional As -As secondary interactions connecting the layers into double sheets. A lateral view of a layer illustrates the structure (Figure 4.1) [8]. 

Supramolecular self-organization, with different amounts of complexity based upon dative bonds (see Section 3.2.3.1) and secondary bonds, is observed for organoindium halides. Long indium-halogen interatomic distances (although shorter than the expected van der Waals distance (ca. 3.8 A for In- -Cl)) are observed for most structurally characterized organoindium halides. 

Compared with organotin compounds, organolead organometallics have been much less investigated by X-ray dil action. There are, however, some well documented examples of supramolecular self-organization in organolead chemistry. 

A similar 1 1 complex, CeEte-SbCT, is fotmed by hexaethylbenzene with antimony trichloride surprisingly this was found to be monomeric, with no supramolecular self-organization [413], There is no obvious reason for this behavior. 

Some other arene-antimony halide complexes have been structurally characterized all have intermolecular secondary Sb - -X interactions and supramolecular self-organization. Examples are naphthalene-2SbCl3 [414], phenanthrene-2SbCl3 [415], pyrene-2SbBr3 [416], and [(SbCl3)2(//- / -[2 ](l,4)cyclophane].v-0,5C6H6 [417], In the naphthalene complex [414] pairs of SbCl3 molecules are interconnected in planar stacks, with shorter primary bonds (axial Sb-Cl 2.367 A, equatorial Sb-Cl 2.347 A) and intermolecular distances Sb- -Cl 3.581-3.832 A. 

On the basis of the data presented it would be highly desirable to investigate more organoantimony derivatives of carboxylic, organophosphoric, and other acids, with very good chances of discovering new supramolecular, self-organized structures. 

Mesitylselenium iodide, 2,4,6-Me3C6H2SeI, has a supramolecular self-organized architecture, 203, based on secondary bonds between iodine and iodine, and between iodine and selenium pairs. Similar self-organization by secondary bonding... 

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