Triangles supramolecular

Treatment of 2,9-dibromophenanthrene with Pt (Et3P)4 followed by bromine-nitrate exchange gave the desired 60° tecton, 2,9-6/i [/ra 5 -Pt(PEt3)2(N03)]phenanthrene, which with different linear connectors afforded a series of self-assembled supramolecular triangles <03JA5193>. A series of related binuclear metallomacrocycles [Cd(N03)2L]2, where L is an angular exo-bidentate, such as 4-(4 -pyridinyl)(2-pyridinylethynyl) benzene, have been reported... 

Figure 1. Supramolecular triangle. R=p-MeOCeH4. Adapted from reference 5. Copyright 2000 American Chemical Society.

Schweiger M, Seidel SR, Arif AM, Stang PJ (2002) Solution and solid state studies of a triangle-square equilibrium anion-induced selective crystallization in supramolecular self-assembly. Inorg Chem 41 2556-2559... 

Precursors based on Mo2" + and Rh2" + cores have been used in combination with dicarboxylate linkers to construct supramolecular arrays. Dimer-of-dimers, trimer-of-dimers (molecular triangles), and tetramer-of-dimers (molecular squares) have been prepared using this approach. Judicious selection of precursors and linkers are essential for the successful synthesis of the desired molecular architectures. A total of twelve dimer-of-dimers (100-111) of general formula [(DAniF)3M02]O2C-X-CO2M02[(DAniF)3] (DAniF = A,A -di(/ -anisyl)formamidinate) have been synthesized in which two M02 units are connected by bridging dicarboxylates. These compounds were prepared in one-pot reactions (Scheme 27). It is important to note that the six equatorial positions of the precursors are blocked in order to... 

The use of inorganic supramolecular compounds in catalysis has also been successful in recent years. Hupp etal. incorporated a Mn(IIl)-porphyrm (see Porphyrin) epoxidation catalyst inside a molecular square, a system that shows enhanced catalyst stabihty and substrate selectivity as compared to the free catalyst. In another example, chiral metaUocyclophanes were constructed from Pt(PEt3)2 units and enantiopme atropoisomeric t,t -binapthyl-6,6 -bis-(acetylenes) and used in enantioselective diethyl zinc addition to aldehydes to afford chiral secondary alcohols. The first organometaUic triangle based on Pt(II) and alkyne-di-substituted-binaphfhyl system was reported and found to effect asymmetric catalysis reactions of aldehydes to alcohols with excellent conversion rates and enantiomeric excess/ ... 

In 1990, using the suitably hindered square-planer metal center [(en)Pd(N03)2] (en=ethylene- 1,2-diamine) and 4,4 -bipyridine, Fujita and coworkers reported the self-assembly of macrocyclic supramolecular squares.Later work revealed that the replacement of 4,4 -bipyridine with more flexible dipyridyl ligands such as trans l,2-bis 4-pyridyl)ethylene resulted in an equilibrating mixture of molecular squares and triangles (Fig. 3). 

Figure 15 Synthesis of a supramolecular tetrahedron 59 from hexa/c/s-ligand 58 to demonstrate directed fiexibiiity. The structure s four individual triangles are highlighted in green (gray, light gray, black and dark gray in print versions) to aid visualization. Adapted with permission from Ref. 15CC3820. Copyright 2015 Royal Society of Chemistry.

Feng X, Liu M, Pisula W, Takase M, Li J, Mullen K (2008) Supramolecular organization and photovoltaics of triangle-shaped discotic graphenes with swallow-tailed alkyl substituents. Adv Mater 20 2684-2689... 

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