Building with Cubane-1,4-diyl. Synthesis of Aryl-Substituted Cubanes, p-[n]Cubyls, and Cubane-Separated Bis(arenes)¹

Abstract

On treatment with an organolithium 1,4-diiodocubane generates cubane-1,4-diyl, a highly reactive species, shown here to be a versatile precursor to numerous aryl substituted cubanes, available now for the first time in high yield. The diyl is demonstrated to provide a good route to bicubyl and its derivatives. A kind of “living polymerization” of the diyl is developed to give the p-[n]cubyls. These oligomers are rigid rods made up of cubanes linked together at the 1 and 4 positions, each cubane adding ∼4.15 Å to the length. The properties of these rods, some more than 15 Å long, are discussed, as are methods for modifying their solubility. X-ray crystallographic analyses of some of these compounds are presented, with emphasis on packing parameters.

Multifunctional imine-POSS as uncommon 3D nanobuilding blocks for supramolecular hybrid materials: synthesis, structural characterization, and properties

“…1 Among the molecules that possess a high degree of symmetry, there are few examples of molecular compounds with functionalities and structures with a high 3D symmetry, such as tetraphenyladamantanes, 2,3 dodecahedral boranes, 4,5 cubanes, 6,7 and tetrasilylmethane derivatives described in their early detailed work by Eaborn and Lickess. It mainly derives from the fact that altering the chemical composition of such NBs via refined synthetic tricks affects the possibility of creating sophisticated interactions between blocks allowing one to tailor global properties exactly at the finest length scales.…”

Synthetic Multifunctional Nanoarchitecture in Lipid Bilayers: Ion Channels, Sensors, and Photosystems

“…For example, from the structural point of view, O-NDIs are just one out of many possible rigid-rod molecules beyond p-oligophenyls that promise access to new structures with new functions. [15][16][17][18][19][20][21][22][23][24][25] The imaginable variability of hoops beyond -sheets in barrel-stave supramolecules simply enormous. Access to transmembrane rigid-rod -stack architecture is naturally not limited to NDI -stacks.…”

“…11,12 Somehow the antithesis to foldamers, 13,14 these simple sturdy rods have attracted considerable scientific attention for applications in the materials sciences. [15][16][17][18][19][20][21][22][23][24][25] Highlights beyond the minimalist oligoacetylenes 17 1 and p-oligophenyls 18,19 2 include the oligonaphthalenes 3 studied in the Tsubaki group because of their exceptional stereochemical complexity ( Fig. 1).…”

“…Eaton's oligocubanes 5 are a spectacular example for a rich collection of non-aromatic and non-planar rigid rods in the literature. 22 Pioneered in the Miller group, rigid oligonaphthalenediimide (O-NDI) rods 6 are of interest because NDIs are one of the few stable organic nsemiconductors. 23 Also of interest in optoelectronics, oligoperylenediimides (O-PDIs) 7 are another example for rigidrod molecules with atoms other than carbon in their scaffold.…”

Cubane: 50 Years Later

“…176 The oligomers are synthesized by reacting cubyllithium 226 with 1,4-diiodocubane (43) in ether, and halogen exchange equilibrium occurs to give 227 and 228. 177 Loss of lithium iodide in compound 228 gives the reactive intermediate cubane-1,4-diyl 47 in very small concentrations. This intermediate then reacts with an equivalent of cubyllithium 226 to give the dicubyllithium product 229.…”