Applications of microscopy and small angle scattering techniques for the characterisation of supramolecular gels

• Connor R. M. MacDonald and
• Emily R. Draper

Beilstein J. Org. Chem. 2024, 20, 2608–2634, doi:10.3762/bjoc.20.220

• fluorescent derivatives to visualise a multicomponent system consisting of neutral and charged gelators (NG and CG, respectively), the self-assembly of neutral and charged fibres (NF and CF, respectively) could be visualised over time. CSLM shows the self-assembly proceeds by the initial self-sorting of NGs

• to assemble NFs. The self-sorting of NFs decreases the concentration of NGs, increasing the relative concentration of CGs, allowing a higher critical assembly concentration of the CGs (arising from electrostatic repulsions between the CGs) to be reached, leading to the co-assembly of CFs. Not only

• could CLSM observe the initial kinetic self-sorting of gelators, but it also showed that the homogenous mixture of NFs and CFs can undergo a higher level of self-sorting, resulting in macroscopic phase separation (Figure 4). To gather a three-dimensional surface profile of a material, AFM utilises a

Heteroleptic metallosupramolecular aggregates/complexation for supramolecular catalysis

• Prodip Howlader and
• Michael Schmittel

Beilstein J. Org. Chem. 2022, 18, 597–630, doi:10.3762/bjoc.18.62

• heteroleptic aggregates are quite different. While in the former often a step-by-step attachment of the different ligands to the metal centers under kinetic control is dominating, the formation of dynamic aggregates relies on effective self-sorting protocols under thermodynamic control [24]. In its initial

• definition, self-sorting describes the capability to distinguish "self" from "non-self" in a mixture of constituents [27][28][29][30], i.e., the formation of well-defined homomeric aggregates [31] instead of a random combination of constituents in the product. This definition was later extended to

• heteromeric complexes by Issacs’ classification [32] of two main categories: (a) social self-sorting, which involves the assembly of different species, and (b) narcissistic self-sorting, which only involves aggregation of the same component. Over the past few years, a variety of social self-sorting protocols

Microwave-assisted multicomponent reactions in heterocyclic chemistry and mechanistic aspects

• Shivani Gulati,
• Stephy Elza John and
• Nagula Shankaraiah

Beilstein J. Org. Chem. 2021, 17, 819–865, doi:10.3762/bjoc.17.71

• microwave irradiation spiked the yield to 84% in 30 min demonstrating the effectiveness of the technological approach. A plausible mechanism including a self-sorting system was suggested. A simple condensation of acyclic 1,3-diketone and amine results in intermediate A formation. The intermediate A

Using multiple self-sorting for switching functions in discrete multicomponent systems

• Amit Ghosh and
• Michael Schmittel

Beilstein J. Org. Chem. 2020, 16, 2831–2853, doi:10.3762/bjoc.16.233

• Amit Ghosh Michael Schmittel Center of Micro and Nanochemistry and Engineering, Organische Chemie I, Universität Siegen, Adolf-Reichwein-Str. 2, D-57068 Siegen, Germany 10.3762/bjoc.16.233 Abstract Over years self-sorting has developed into a powerful tool in supramolecular chemistry, for

• instance, to promote the error-free formation of intricate multicomponent assemblies. However, in order to use the enormous potential of self-sorting for sophisticated information processing more recent developments have focused on the reversible reconfiguration of multicomponent systems driven by multiple

• self-sorting protocols. The present mini review will provide an overview over the latest advancements in this field with a focus on reversibly switchable functions in discrete supramolecular systems. Keywords: copper; fluorescence; self-assembly; self-sorting; zinc porphyrin; Introduction Since self

A chiral self-sorting photoresponsive coordination cage based on overcrowded alkenes

• Constantin Stuckhardt,
• Diederik Roke,
• Wojciech Danowski,
• Edwin Otten,
• Sander J. Wezenberg and
• Ben L. Feringa

Beilstein J. Org. Chem. 2019, 15, 2767–2773, doi:10.3762/bjoc.15.268

• supramolecular coordination complexes consisting of a Pd2L4 stoichiometry. As shown by NMR, CD and X-ray studies, as well as DFT calculations, these complexes form cage-like structures by chiral self-sorting. Photochromic ligands derived from first generation molecular motors enable light-driven interconversion

• switches have not been reported in the literature. In chiral self-sorting SCCs, either homo- or heterochiral complexes are formed exclusively through high fidelity recognition of the components within the complex [31][32][33]. The formation of such complexes with high selectivity and well-defined chirality

• formed revealing that a chiral self-sorting process takes place. In addition, two of the cage isomers can bind a tosylate anion in solution by formation of a host–guest complex. Results and Discussion Ligands Z-1 and E-1 (Scheme 1) were synthesized by a Suzuki cross-coupling reaction of 3

Nanopatterns of arylene–alkynylene squares on graphite: self-sorting and intercalation

• Tristan J. Keller,
• Joshua Bahr,
• Kristin Gratzfeld,
• Nina Schönfelder,
• Marcin A. Majewski,
• Marcin Stępień,
• Sigurd Höger and
• Stefan-S. Jester

Beilstein J. Org. Chem. 2019, 15, 1848–1855, doi:10.3762/bjoc.15.180

• graphite and 1,2,4-trichlorobenzene. Self-sorting leads to the intermolecular interdigitation of alkoxy side chains of identical length. Voids inside and between the squares are occupied by intercalated solvent molecules, which numbers depend on the sizes and shapes of the nanopores. In addition, planar

• and non-planar coronoid polycyclic aromatic hydrocarbons (i.e., butyloxy-substituted kekulene and octulene derivatives) are found to be able to intercalate into the intramolecular nanopores. Keywords: macrocycles; scanning tunneling microscopy; self-assembled monolayers; self-sorting; solid/liquid

• other words, either alkyl/alkoxy chains of the same or different length(s) will interdigitate, which corresponds to narcisstic self-sorting or social self-sorting, respectively [26]. Results and Discussion Here, we report on the synthesis and supramolecular nanopatterns of shape-persistent arylene

Selective detection of DABCO using a supramolecular interconversion as fluorescence reporter

• Indrajit Paul,
• Debabrata Samanta,
• Sudhakar Gaikwad and
• Michael Schmittel

Beilstein J. Org. Chem. 2019, 15, 1371–1378, doi:10.3762/bjoc.15.137

• Indrajit Paul Debabrata Samanta Sudhakar Gaikwad Michael Schmittel Center of Micro and Nanochemistry and Engineering, Organische Chemie I, Universität Siegen, Adolf-Reichwein-Str. 2, D-57068 Siegen, Germany 10.3762/bjoc.15.137 Abstract The quantitative double self-sorting between the three

• compounds. Keywords: copper; detection; fluorescence; interconversion; macrocycles; self-assembly; self-sorting; zinc porphyrin; Introduction Since dynamic multicomponent supramolecular structures are nowadays abundant [1][2], the weak intercomponent binding [3][4][5][6][7][8][9] is often instrumentalized

• dual-state supramolecular transformation driven by addition/removal of DABCO (4) and it requires a transition between completive vs incomplete self-sorting [27][28]. The fact that DABCO (4) exclusively drives the supramolecular interconversion was further developed into a fluorescent reporter system

Mechanochemistry of supramolecules

• Anima Bose and
• Prasenjit Mal

Beilstein J. Org. Chem. 2019, 15, 881–900, doi:10.3762/bjoc.15.86

• example of a metal-directed self-assembly is shown [44]. The mixing of diacetyl and 2-aminoethanethiol led to a dynamic mixture of products including 1. The square-planar directing metal ion nickel(II) induces the formation of cyclic product 2 through a process called self-sorting [51][52][53

• conventional materials [75][76]. The systems chemistry approach may give easy access to new structures or functional materials simply by controlling the inputs of a multicomponent system. The concept of self-sorting [77][78][79] and subcomponent self-assembly approach [80] are well-developed methods being

• through self-sorting led to three structurally different metallosupramolecular Fe(II) complexes. Under mechano-milling conditions the tetranuclear [Fe4(AD2)6]4− 22-component cage 26, dinuclear [Fe2(BD2)3]2− 11-component self-assembled helicate 27 and 5-component mononuclear [Fe(CD3)]2+ complex 28 could be

Synthesis and supramolecular self-assembly of glutamic acid-based squaramides

• Juan V. Alegre-Requena,
• Marleen Häring,
• Isaac G. Sonsona,
• Alex Abramov,
• Eugenia Marqués-López,
• Raquel P. Herrera and
• David Díaz Díaz

Beilstein J. Org. Chem. 2018, 14, 2065–2073, doi:10.3762/bjoc.14.180

• agreement with our previous observations made with a different squaramide, where we hypothesized that ultrasound could help to preserve only the thermodynamically more stable aggregates through a self-sorting mechanism, thus providing a more robust starting platform for rebuilding the gel network [21]. At

Organic chemistry meets polymers, nanoscience, therapeutics and diagnostics

• Vincent M. Rotello

Beilstein J. Org. Chem. 2016, 12, 1638–1646, doi:10.3762/bjoc.12.161

• structures [19]. Through quite a bit of experimentation we determined that the unprecedented self-assembly process was driven by self-sorting of the polymer chains to provide vesicle walls with denser recognition elements in the middle than at the outside [20]. While we were working with polymers, we were

Supramolecular structures based on regioisomers of cinnamyl-α-cyclodextrins – new media for capillary separation techniques

• Gabor Benkovics,
• Ondrej Hodek,
• Martina Havlikova,
• Zuzana Bosakova,
• Pavel Coufal,
• Milo Malanga,
• Eva Fenyvesi,
• Andras Darcsi,
• Szabolcs Beni and
• Jindrich Jindrich

Beilstein J. Org. Chem. 2016, 12, 97–109, doi:10.3762/bjoc.12.11

• that the cavity of the CD shows distinguishable inclusion affinities towards different substrates, even to homologues and isomers. A self-sorting complex formation ability was described for the two regioisomers of monocinnamoyl-α-CD (Cio-α-CD) [9]. While the 2-Cio-α-CD isomer formed an insoluble double

• -threaded supramolecular dimer in water, the 3-Cio-α-CD formed a soluble supramolecular oligomer in the same solvent. The mixture of both regioisomers led to the formation of a self-sorting oligomeric system, where only the heterosupramolecular interactions between the two isomers were present but the

Discrete multiporphyrin pseudorotaxane assemblies from di- and tetravalent porphyrin building blocks

• Mirko Lohse,
• Larissa K. S. von Krbek,
• Sebastian Radunz,
• Suresh Moorthy,
• Christoph A. Schalley and
• Stefan Hecht

Beilstein J. Org. Chem. 2015, 11, 748–762, doi:10.3762/bjoc.11.85

• ] to life science [13][14][15][16][17] have benefited from the development of the basic concepts of molecular recognition, templation [18], self-assembly [19], or self-sorting [20][21], just to name a few. More recently, multivalent binding [22][23][24] and cooperativity [25][26] have attracted

Self-assembly of heteroleptic dinuclear metallosupramolecular kites from multivalent ligands via social self-sorting

• Christian Benkhäuser and
• Arne Lützen

Beilstein J. Org. Chem. 2015, 11, 693–700, doi:10.3762/bjoc.11.79

• social self-sorting manner as evidenced by NMR spectroscopy and mass spectrometry. Keywords: metal complexes; multivalency; self-assembly; self-sorting; supramolecular chemistry; Tröger's base; Introduction Self-assembly of defined aggregates from multicomponent mixtures through self-sorting effects

• has become an important issue in supramolecular chemistry [1][2][3][4][5]. Such self-sorting can either occur in a social self-discriminating or a narcissistic self-recognition manner (Scheme 1). In general, geometrical size and shape complementarity are used to ensure high-fidelity self-sorting. This

• of metallosupramolecular aggregates from multivalent rigid concave ligand structures through (chiral) self-sorting processes [16][17][18][19][20][21][22][23], we were wondering whether we could yet establish another approach to achieve the formation of heteroleptic metallosupramolecular assemblies in

Self-assembly of metallosupramolecular rhombi from chiral concave 9,9’-spirobifluorene-derived bis(pyridine) ligands

• Rainer Hovorka,
• Sophie Hytteballe,
• Torsten Piehler,
• Georg Meyer-Eppler,
• Filip Topić,
• Kari Rissanen,
• Marianne Engeser and
• Arne Lützen

Beilstein J. Org. Chem. 2014, 10, 432–441, doi:10.3762/bjoc.10.40

• . Keywords: concave templates; metal complexes; self-assembly; self-sorting; 9,9’-spirobifluorene; supramolecular chemistry; Introduction Concave templates are versatile tools to achieve self-sorting behaviour in the self-assembly of defined aggregates from multicomponent mixtures in a social self

• -discrimination or a narcissistic self-recognition manner [1][2][3]. Usually, geometrical size and shape complementarity are employed to ensure such self-sorting. However, these factors do not account in self-sorting processes where enantiomers are involved whose shape and size does not vary but only their

• relative spatial orientation. Hence, chiral self-sorting is a truly challenging task and high-fidelity chiral self-sorting processes have been observed in a rather limited number of examples for the formation of stereochemically defined metallosupramolecular aggregates from racemic ligands in a self

Self-assembly of Ru₄ and Ru₈ assemblies by coordination using organometallic Ru(II)₂ precursors: Synthesis, characterization and properties

• Sankarasekaran Shanmugaraju,
• Dipak Samanta and
• Partha Sarathi Mukherjee

Beilstein J. Org. Chem. 2012, 8, 313–322, doi:10.3762/bjoc.8.34

• donor (Scheme 1) [11]. Instead, the exclusive formation of two tetranuclear assemblies (2a, 2b) upon mixing of binuclear Ru(II)2 acceptors 1a or 1b with an imidazole-based tetratopic donor L is interesting. The exclusive self-sorting of tetranuclear macrocycles (2a and 2b) rather than the expected

• tetranuclear rectangular geometry with the dimensions of 5.53 Å × 12.39 Å. Furthermore, the photo- and electrochemical properties of these newly synthesized assemblies have been studied by using UV–vis absorption and cyclic voltammetry analysis. Keywords: cages; macrocycles; ruthenium(II); self-assembly; self

• -sorting; Introduction Self-assembly of metal-based molecular architectures through coordination has emerged as an active field of research as large numbers of intricate structural motifs can easily be derived in a single step from predesigned molecular building units. In the last two decades several

Synthesis of multivalent host and guest molecules for the construction of multithreaded diamide pseudorotaxanes

• Nora L. Löw,
• Egor V. Dzyuba,
• Boris Brusilowskij,
• Lena Kaufmann,
• Elisa Franzmann,
• Wolfgang Maison,
• Emily Brandt,
• Daniel Aicher,
• Arno Wiehe and
• Christoph A. Schalley

Beilstein J. Org. Chem. 2012, 8, 234–245, doi:10.3762/bjoc.8.24

• these concepts are not only molecular recognition and the noncovalent bonds themselves, but also self-assembly, self-sorting, templation and multivalent binding [1][2][3][4][5][6][7][8]. Consequently, the reductionist investigation of synthetic supramolecules can help us to understand biological systems

Impact of the level of complexity in self-sorting: Fabrication of a supramolecular scalene triangle

• Kingsuk Mahata and
• Michael Schmittel

Beilstein J. Org. Chem. 2011, 7, 1555–1561, doi:10.3762/bjoc.7.183

• Kingsuk Mahata Michael Schmittel Center of Micro- and Nanochemistry and Engineering, Organische Chemie I, Universität Siegen, Adolf-Reichwein-Straße, D-57068 Siegen, Germany 10.3762/bjoc.7.183 Abstract The impact of the level of complexity in self-sorting was elaborated through the fabrication of

• various scalene triangles. It turned out that the self-sorting system with a higher level of complexity was far superior to less complex sorting algorithms. Keywords: copper; metallosupramolecular chemistry; phenanthroline; self-assembly; self-sorting; Introduction Self-assembly guided by self-sorting

• algorithms has received considerable attention over the past two decades as such protocols pave the way for intricate supramolecular assemblies [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. However, despite its wide use, the definition of self-sorting remains vague with no precise

Supramolecular chemistry II

• Christoph A. Schalley

Beilstein J. Org. Chem. 2011, 7, 1541–1542, doi:10.3762/bjoc.7.181

• sciences on the other. In the life sciences, the networks of noncovalent interactions between the constituents of cells, for example, have shifted into the current focus. Self-assembly, templation, self-sorting and multivalent binding all contribute to setting up the extremely complex architecture of a

Templated versus non-templated synthesis of benzo-21-crown-7 and the influence of substituents on its complexing properties

• Wei Jiang and
• Christoph A. Schalley

Beilstein J. Org. Chem. 2010, 6, No. 14, doi:10.3762/bjoc.6.14

• binding mode. Compared to dibenzo-24-crown-8, the complexing properties of benzo-21-crown-7 turn out to be more susceptible to modifications at the crown periphery. Keywords: benzo-21-crown-7; pseudorotaxane; self-sorting; supramolecular chemistry; template; Introduction Mechanically interlocked

• construction of a four-component self-sorting system based on the fact that C7 cannot pass over a phenyl stopper group at the end of a dialkylammonium axle, while DB24C8 can [26]. This system was further extended to construct more complex multiply interlocked structures by using the strategy of integrative

• self-sorting [26][27] which ensures programmability and positional control of all distinct subunits present in the complexes. Along this line, more diverse and complex supramolecular structures could be obtained when suitable instructions are written into the structures of their components

Thematic series on supramolecular chemistry

• Christoph A. Schalley

Beilstein J. Org. Chem. 2009, 5, No. 76, doi:10.3762/bjoc.5.76

• successfully transferred to neutral and anionic hosts. Nowadays, multivalent interactions start to play a significant role for host-guest chemistry. But supramolecular chemistry is much more than molecular recognition. Concepts such as templated synthesis, (hierarchical) self-assembly, and self-sorting have