Eine Salicylbisimin‐Käfigverbindung mit großer spezifischer Oberfläche und selektiver CO₂/CH₄‐Adsorption

Periphery‐Substituted [4+6] Salicylbisimine Cage Compounds with Exceptionally High Surface Areas: Influence of the Molecular Structure on Nitrogen Sorption Properties

“…In the 13 C MAS NMR spectrum of cage compound 3 a sharp signals can be detected, which is in good agreement with the prior findings that the as-synthesized material is microcrystalline. [26] Four major signals of the methinyl carbons of the triptycene bridgeheads can be detected at d 53.3, 53.9, 55.1 and 55.6 ppm, with two different signal intensities. Exactly this pattern is expected, if a C 3v -symmetric "frozen" conformational molecular structure is assumed, according to the X-ray crystal structure analysis.…”

“…[28] The single-crystal X-ray structure of cage compound 3 a, crystallized from hot DMSO, revealed that the cage molecules are shape-persistent in the crystalline phase and are assembled to each other mainly by p-p interaction of the salicylbisimine subunits of adjacent molecules. [26] In addition, a weak interaction of the tert-butyl groups to the phenolic hydroxyl groups between adjacent Scheme 1. One-pot synthesis of an endo-functionalized [4 + 6] cage compound 3 a via 12-fold condensation of triamine 1 and commercially available salicyldialdehyde 2 a.…”

“…, measured by nitrogen sorption at 77.35 K. [26] This is to the best of our knowledge the highest value among porous materials, consisting of discrete molecules, including metal-organic polyhedra (MOPs). [27,6] The material adsorbs CO 2 (9.4 wt % at 1 bar and 273 K) preferably to methane (0.98 wt % at 1 bar and 273 K) and 1.1 wt % H 2 at 77 K and 1 bar, which is comparable or even higher than the adsorption properties of a number of MOFs, COFs and related porous compounds.…”

Rational Design of Multifunctional Nanopores by Mixing Matching Molecules

“…[7] In just two years the values of specific surface areas were approximately doubled for such systems. [8] Today, the highest value for BET surface areas for an organic crystalline system, consisting exclusively of discrete organic compounds, is 2071 m 2 g À1 , [9] and further improvements can be expected. But surface area alone is just one parameter of porous compounds and not the only feature that makes porous systems interesting for several applications, such as gas storage/separation, or catalysis.…”

Postmodifizierung der Hohlräume poröser formstabiler organischer Käfigverbindungen

“…[3][4][5] Kürzlich wurde gezeigt, dass Materialien, die ausschließlich aus organischen Käfigverbindungen aufgebaut sind, eine außerordentliche permanente Porosität aufweisen kçnnen, mit sehr hohen spezifischen Oberflächen und guten Gassorptionseigenschaften sowohl im kristallinen als auch im amorphen Zustand. [6][7][8] Ein herausragendes Merkmal porçser Materialien auf Basis molekularer Käfige, das sie von anderen porçsen ausgedehnten Netzwerkstrukturen wie Metall-organischen oder kovalent-organischen Gerüstverbindungen unterscheidet, ist die Lçslichkeit der intrinsisch porçsen molekularen Einheiten. [9] Dies erçffnet eine Reihe von Mçglichkeiten, die mit ausgedehnten Netzwerkstrukturen nur schwierig zu erreichen oder gar unmçglich sind.…”