Controllable Self-Assembly of Pills and Cages via Imine Condensation for Silver Cation Detection

Abstract

By condensing a trisamino linker with one of the two analogous bisaldehyde ligands, pills and tetrahedrons could be self-assembled. The self-assembled preference could be controlled by tuning the reaction conditions, including the size of side chain, concentration, and temperature. Coordination of silver cation quenches the fluorescence of the fluorene moieties on the pill, opening up opportunities for Ag+ cation detection.

Size-Selective Catalytic Polymer Acylation with a Molecular Tetrahedron

“…Here, we now show that-due to their wide openings-tetrahedral cages allow polymers with bulky side chains to thread through, preparing for further catalytic functionalization. Although molecular polyhedra with T d symmetry can be synthesized [23][24][25][26][27][28] with dynamic covalent chemistry (e.g., with imine linkages), 23,[29][30][31][32][33][34][35][36][37][38] the currently reported systems likely lack sufficient stability 39,40 for organocatalytic PSPM processes. 41 While hydrolytic stability can be imparted onto imine-linked cages by reduction of the imines to amines, 37,38,42 the secondary amines formed upon reduction are good nucleophiles, which might engage in side reactions under the acylation conditions employed in this work.…”

Soluble Congeners of Prior Insoluble Shape‐Persistent Imine Cages

“…Nowadays, shape‐persistent organic cages are mainly synthesized by using reversible condensation reactions, such as by multiple imine bond formation or the generation of boronic esters from the corresponding diols and boronic acids [20–60] . These reactions used are often called dynamic covalent chemistry (DCC) reactions, allowing the system to reach thermodynamic equilibrium by self‐correction mechanisms due to the intrinsic reversibility [5,61,62] .…”

“…Nowadays, shape‐persistent organic cages are mainly synthesized by using reversible condensation reactions, such as by multiple imine bond formation or the generation of boronic esters from the corresponding diols and boronic acids. [ 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 ] These reactions used are often called dynamic covalent chemistry (DCC) reactions, allowing the system to reach thermodynamic equilibrium by self‐correction mechanisms due to the intrinsic reversibility. [ 5 , 61 , 62 ] However, not always is the formed cage also the favored product of thermodynamic equilibrium and the equilibrium needs to be shifted by either removing product by precipitation or, in case of formed water, by Dean‐Stark traps or other scavengers (e. g. molecular sieves).…”

Cucurbitimines – imine cages with concave walls

“…[1][2][3][4][5][6] Although a few examples of boronic ester cages, or those based on disulphide formation or other DCC reactions are known, [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] no doubt, the vast majority of shape-persistent organic cages is relying on the use of multiple imine condensation reactions, 1 which bear the advantage to be transformed further to convert these to chemically robust cages, [27][28][29][30][31] which is for the other type of DCC reactions difficult or even impossible. 32 Among those imine cages, shapes, such as trigonal prisms, [33][34][35] tetrahedra, [36][37][38][39] truncated tetrahedra, 40,41 cubes, [42][43][44][45][46] tetrapods,…”