A Tetrameric Cage with D_2h Symmetry through Alkyne Metathesis

Abstract

Shape-persistent covalent organic polyhedrons (COPs) with ethynylene linkers are usually prepared through kinetically controlled cross-coupling reactions. The high-yielding synthesis of ethynylene-linked rigid tetrameric cages via one-step alkyne metathesis from readily accessible triyne precursors is presented. The tetrameric cage contains two macrocyclic panels and exhibits D2h symmetry. The assembly of such a COP is a thermodynamically controlled process, which involves the initial formation of macrocycles as key intermediates followed by the connection of two macrocycles with ethynylene linkages. With a large internal cavity, the cage exhibits a high binding selectivity toward C70 (K = 3.9×10(3) L mol(-1)) over C60 (no noticeable binding).

Topological landscapes of porous organic cages

“…In Fig. 6 69 The component BB has a C 3 symmetry axis and therefore reduced symmetry in the BB need not necessarily be employed to reach this topology if BB flexibility can account for this. This topology should be achievable through two-component DCC reactions.…”

Molybdenum Alkylidyne Complexes with Tripodal Silanolate Ligands: The Next Generation of Alkyne Metathesis Catalysts

“…[20,21] This system suffers from the internal coordination of the basic N-atom onto the molybdenum center, which compromises the Lewis acidity of the alkylidyne unit. [24][25][26] It is against this backdrop that the current study must be seen. [23] Forthe lack of the anchoring N-atom, however, more than one active species is generated on reaction with 3; rigorous proof of formation of well-defined catalysts of podand topology is missing for any of these systems.…”

Kovalente organische Netzwerke und Käfigverbindungen: Design und Anwendungen von polymeren und diskreten organischen Gerüsten

“…[110][111][112][113][114] Da die C-C-Bindungsknüpfung in diesem Fall nur in Gegenwart eines Katalysators reversibel ist, sind solche Ansätze besonders fürd ie Synthese von stabilen Käfigen interessant. Alkinmetathese wurde in einigen Beispielen für die Synthese von formgetreuen molekularen Käfigen genutzt.…”