Vielfalt und Komplexität durch reversible vielfach‐orthogonale Wechselwirkungen in Mehrkomponentensystemen

Schmittel, Michael; Mahata, Kingsuk

doi:10.1002/ange.200800583

Cited by 29 publications

(5 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Recently, we described a first success in this direction: a 52membered macrocycle was obtained by the concomitant formation of reversible imine, boronate ester, and rheniumnitrogen bonds. [11,12] Herein, we describe how the polycondensation of triamines with metallamacrocyclic building blocks, containing pendent aldehyde groups, has enabled the facile synthesis of several new nanoscopic cages.The reaction of a triamine with a trialdehyde can result in the formation of a [4+4] condensation product, provided that the reactants have complementary shape and rigidity. We hypothesized that it should be possible to make expanded structures by replacing either the triamine or the trialdehyde with trinuclear metallamacrocycles having appropriate amine or aldehyde functionalities in their ligand peripheries.…”

mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Combining Metallasupramolecular Chemistry with Dynamic Covalent Chemistry: Synthesis of Large Molecular Cages

et al. 2010

View full text Add to dashboard Cite

Molecular cages with large internal voids are best synthesized by assembly of multiple building blocks under thermodynamic control. To connect the building blocks, metal-ligand interactions are commonly employed. [1] The resulting coordination cages have found numerous applications. For example, they can be used as nanoreactors for chemical transformations, as delivery agents for anticancer compounds, or for the stabilization of highly reactive guest molecules. [1] The assembly of purely organic cages can be achieved using dynamic covalent chemistry. [2][3][4][5][6] Along these lines, imine condensations have been most widely used to date, [3] but the syntheses of cages based on boronic ester condensations, [4] thiol-disulfide exchange reactions, [5] or olefin metathesis [6] have also been described. Metallasupramolecular chemistry has been successfully merged with dynamic covalent chemistry by performing imine condensations in the first coordination sphere of metal ions. [7] This approach has proven extremely robust due to the resulting mutual stabilization of both the metal complex and the imine bond. [8] Fascinating recent results include the stabilization of molecular P 4 within a coordination cage, [9] and the synthesis of a Borromean ring and a Solomon knot. [10] Our group is interested in synthesizing complex molecular architectures by combining metallasupramolecular chemistry with dynamic covalent chemistry in an orthogonal fashion. Recently, we described a first success in this direction: a 52membered macrocycle was obtained by the concomitant formation of reversible imine, boronate ester, and rheniumnitrogen bonds. [11,12] Herein, we describe how the polycondensation of triamines with metallamacrocyclic building blocks, containing pendent aldehyde groups, has enabled the facile synthesis of several new nanoscopic cages.The reaction of a triamine with a trialdehyde can result in the formation of a [4+4] condensation product, provided that the reactants have complementary shape and rigidity. We hypothesized that it should be possible to make expanded structures by replacing either the triamine or the trialdehyde with trinuclear metallamacrocycles having appropriate amine or aldehyde functionalities in their ligand peripheries. To implement such a reaction, we synthesized the formylsubstituted 3-hydroxy-2-pyridone ligand 1 (Scheme 1) using standard organic transformations (Supporting Information). Subsequent reaction with [{(arene)RuCl 2 } 2 ] complexes in the presence of base gave the trinuclear macrocycles 2 a (arene = p-cymene) and 2 b (arene = 1,3,5-Me 3 C 6 H 3 ; Scheme 1). The spectroscopic features of 2 a and 2 b were similar to what has been reported for other organometallic trimers with bridging 3-hydroxy-2-pyridone ligands; [13] moreover, crystallographic analysis of 2 b confirmed that a trinuclear complex had formed (Supporting Information, Figure S1). [14] The three aldehyde groups are 7.8 apart (average O···O distance) and oriented towards the same face of the macrocyclic framework. Scheme 1...

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

Combining Metallasupramolecular Chemistry with Dynamic Covalent Chemistry: Synthesis of Large Molecular Cages

et al. 2010

View full text Add to dashboard Cite

show abstract

“…General procedure for the preparation of 1 a, 1 b, and 1 c: A mixture of an oligo(ethylene glycol) bis-toluenesulfonate ( 9, 161.2, 144.7, 136.4, 132.9, 129.8, 127.9, 113.9, 83.5, 70.7, 69.6, 69.2, 68.6, 67.1, 24.8, 21.6 ppm; ESI-HRMS: m/z calcd for C 25 (d, J = 8.4 Hz, 2 H), 6.88-6.91 (d,J = 8.7 Hz,2 H),4 H), 3.83-3.85 (m, 2 H), 3.58-3.71 (m, 10 H), 2.43 (s, 3 H), 1.33 ppm (s, 12 H); 13 C NMR (CDCl 3 , 75 MHz): d = 161.3, 161.2, 144.7, 136.4, 132.9, 129.8, 127.9, 113.9, 83.5, 70.7, 70.6, 69.6, 69.2, 68.6, 67.1, 24.8, 21.6 (d,J = 8.4 Hz,2 H),J = 8.7 Hz,2 H),J = 8.4 Hz, 2 H), 6.88-6.91 (d,J = 8.7 Hz,2 H),4 H), 3.85-3.87 (m, 2 H), 3.58-3.71 (m, 14 H), 2.44 (s, 3 H), 1.33 ppm (s, 12 H); 13 C NMR (CDCl 3 , 75 MHz): d = 160.9, 161.2, 144.8, 136.0, 132.5, 129.4, 127.5, 113.4, 83.1, 70.3, 70.1, 69.1, 68.9, 68.1, 66.7, 24.5, 21.2 General procedure for the preparation of 2 a, 2 b, and 2 c: A mixture of 2,6-dibromobenzaldehyde (1.73 mmol), boronic ester 1 a, 1 b, or 1 c, Na 2 CO 3 (2 m, 6.90 mmol), and [PdA C H T U N G T R E N N U N G (PPh 3 ) 4 ] (0.173 mmol) in THF (50 mL) and deionized water (5 mL) was heated at reflux overnight under nitrogen. The mixture was extracted with ethyl acetate.…”

Section: Methodsmentioning

confidence: 99%

Smart Macrocyclic Molecules: Induced Fit and Ultrafast Self‐Sorting Inclusion Behavior through Dynamic Covalent Chemistry

Han¹,

Pan²,

Lei³

et al. 2010

Chemistry A European J

View full text Add to dashboard Cite

A family of macrocycles with oligo(ethylene glycol) chains, 4O, 5O, and 6O, was developed to construct a series of new incorporated macrocycles through dynamic covalent chemistry. These flexible macrocycles exhibited excellent "self-sorting" abilities with diamine compounds, which depended on the "induced-fit" rule. For instance, the host macrocycles underwent conformational modulation to accommodate the diamine guests, affording [1+1] intramolecular addition compounds regardless of the flexibility of the diamine. These macrocycles folded themselves to fit various diamines with different chain length through modulation of the flexible polyether chain, and afforded intramolecular condensation products. However, if the chain of the diamine was too long and rigid, oligomers or polymers were obtained from the mixture of the macromolecule and the diamine. All results demonstrated that inclusion compounds involving conformationally suitable aromatic diamines were thermodynamically favorable candidates in the mixture due to the restriction of the macrocycle size. Furthermore, kinetic and thermodynamic studies of self-sorting behaviors of both mixed 4O-5O and 4O-6O systems were investigated in detail. Finally, theoretical calculations were also employed to further understand such self-sorting behavior, and indicated that the large enthalpy change of H(2)NArArNH(2)@4O is the driving force for the sorting behavior. Our system may provide a model to further understand the principle of biomolecules with high specificity due only to their conformational self-adjusting ability.

show abstract

“…What is the limitation in terms of size and complexity? [67] Until now, the maximum number of components that have been used for the building of one molecular cage is three. The number of different bond types is two (if additional supramolecular interactions are not taken into account).…”

Section: Conclusion and Future Perspectivesmentioning

confidence: 99%

Shape‐Persistent Organic Cage Compounds by Dynamic Covalent Bond Formation

2010

View full text Add to dashboard Cite

One area of supramolecular chemistry involves the synthesis of discrete three-dimensional molecules or supramolecular aggregates through the coordination of metals. This field also concerns the chemistry of supramolecular cage compounds constructed through the use of such coordination bonds. To date, there exists a broad variety of supramolecular cage compounds; however, analogous organic cage compounds formed with only covalent bonds are relatively rare. Recent progress in this field can be attributed to important advances, not least the application of dynamic covalent chemistry. This concept makes it possible to start from readily available precursors, and in general allows the synthesis of cage compounds in fewer steps and usually higher yields.

show abstract

Vielfalt und Komplexität durch reversible vielfach‐orthogonale Wechselwirkungen in Mehrkomponentensystemen

Cited by 29 publications

References 35 publications

Combining Metallasupramolecular Chemistry with Dynamic Covalent Chemistry: Synthesis of Large Molecular Cages

Combining Metallasupramolecular Chemistry with Dynamic Covalent Chemistry: Synthesis of Large Molecular Cages

Smart Macrocyclic Molecules: Induced Fit and Ultrafast Self‐Sorting Inclusion Behavior through Dynamic Covalent Chemistry

Shape‐Persistent Organic Cage Compounds by Dynamic Covalent Bond Formation

Contact Info

Product

Resources

About