Ship-in-a-Bottle Synthesis of Otherwise Labile Cyclic Trimers of Siloxanes in a Self-Assembled Coordination Cage

Yoshizawa, Michito; Kusukawa, Takahiro; Fujita, Makoto; Yamaguchi, Kentaro

doi:10.1021/ja000779c

Cited by 316 publications

(156 citation statements)

References 21 publications

Supporting

Mentioning

142

Contrasting

Unclassified

Order By: Relevance

“…After addition of the second equivalent of metal precursor the 1 H NMR spectrum showed the signals of the cage as the only product. The same behavior has been observed in the case of cavitand 2b plus Pd(en)(NO 3 ) 2 in DMSO-d 6 as solvent (Fig. 3).…”

Section: Resultssupporting

confidence: 82%

“…cavitands M etal-directed self-assembly has been widely used to construct three-dimensional structures presenting internal cavities of molecular dimensions, capable of trapping ions and neutral molecules (1,2). The ability of such container molecules to confine (3) and stabilize (4) their guests makes them particularly attractive for many potential applications ranging from catalysis (5,6) to nanotechnology (for self-assembly in nanotechnology, see ref. 7; ref.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Design and self-assembly of wide and robust coordination cages

Pirondini

Bertolini

Cantadori

et al. 2002

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

The self-assembly of a new class of coordination cages formed from two tetrapyridyl-substituted cavitands connected through four square-planar palladium or platinum complexes is reported. The shape of the internal cavity resembles an ellipsoid with a calculated volume of 840 Å 3 . The four lateral portals have a diameter of about 6 Å, large enough to allow the fast entrance͞ egress of counterions in solution. The platinum cages 3a,e cannot be disassembled using triethylamine as competitive ligand and they are kinetically stable at room temperature, whereas the palladium cages 3b-d, 3f-h are disassembled and kinetically labile under the same conditions. The different solubility properties of the cage components have allowed the extension of this selfassembly protocol to the liquid-liquid interface. cavitands M etal-directed self-assembly has been widely used to construct three-dimensional structures presenting internal cavities of molecular dimensions, capable of trapping ions and neutral molecules (1, 2). The ability of such container molecules to confine (3) and stabilize (4) their guests makes them particularly attractive for many potential applications ranging from catalysis (5, 6) to nanotechnology (for self-assembly in nanotechnology, see ref. 7; ref. 8). Specifically, surface-controlled self-assembly is rapidly emerging as a valuable tool for the generation of complex structures directly on solid supports (9-11). Unlike the covalent approach used for carcerands synthesis (12), the thermodynamic control of the process conveys interesting features, among which reversibility (13), selection (14), and self-repairing properties are the most interesting.Cavitand-based coordination cages are receiving increasing attention because of the versatility of cavitand platforms in terms of preorganization and synthetic modularity (15)(16)(17)(18)(19)(20). Strong metal-ligand interactions are necessary to operate cage selfassembly (CSA) in a wide range of solvents, to extend further these self-assembly protocols to solid-liquid and liquid-liquid interfaces.For this purpose we designed and synthesized new cavitands bearing pyridines (for references on cages derived from multidentate pyridine ligands, see ref. 21; refs. 22 and 23) instead of nitriles (24) at the upper rim as ligands for the coordination to the metal centers. CSA requires a cavitand with four pyridines preorganized in a diverging spatial orientation, pointing outward (o) the cavity, being designated the oooo isomer (for in͞out isomerism in cavitands, see ref. 25). Materials and MethodsGeneral. All commercial reagents were ACS reagent grade and used as received. All solvents were dried over 3-and 4-Å molecular sieves. Resorcinarenes 1a,b were prepared according to the literature (26). Metal precursors were prepared from the corresponding dichlorobis derivatives following established procedures (27-29). 1 H NMR were recorded on Bruker (Billerica, MA) AC300 (300 MHz) and AMX400 (400 MHz) spectrometers and all chemical shifts (␦) were reported in parts per milli...

show abstract

Section: Resultssupporting

confidence: 82%

mentioning

confidence: 99%

Design and self-assembly of wide and robust coordination cages

Pirondini

Bertolini

Cantadori

et al. 2002

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…The use of supramolecular assemblies as reaction vessels is emerging as a new direction in the field (27)(28)(29)(30)(31)(32). The hostguest properties of each assembly dictate which chemical reactions will be suited for transfer from macroscale to nanoscale containers.…”

Section: Host-guest Chemistry and Nanoscale Reaction Vesselsmentioning

confidence: 99%

Supramolecular assembly dynamics

Davis

Yeh²,

Raymond³

2002

Proc. Natl. Acad. Sci. U.S.A.

223

132

View full text Add to dashboard Cite

“…They are also promising with regard to nanotechnologies involving drug delivery, clean chemical synthesis, assembly of novel materials, and separation science. [4][5][6][7] Despite keen interest in the self-assembly of simple organic building blocks into molecular containers, there is generally little information on the fate of the encapsulated guest molecules. [8][9][10] Although the confined guest matrix within these molecular containers has been regarded as a new phase of matter, [11] a detailed understanding of the interplay and relative orientations of the constituent guest molecules has, until now, been restricted to a few instances of limited complexity.…”

mentioning

confidence: 99%