Molecular paneling via coordination

Fujita, Makoto; Umemoto, Kazuhiko; Yoshizawa, Michito; Fujita, Norifumi; Kusukawa, Takahiro; Biradha, Kumar

doi:10.1039/b008684n

Cited by 898 publications

(444 citation statements)

References 40 publications

Supporting

Mentioning

424

Contrasting

Unclassified

Order By: Relevance

“…A rtificial supramolecular hosts with stable and well defined structures formed by spontaneous self-assembly of molecular building blocks in organic solvents have shown great potential for inclusion phenomena, molecular recognition, or catalysis (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12). However, supramolecular complexes that operate in aqueous solution are rare (10)(11)(12)(13)(14).…”

mentioning

confidence: 99%

“…However, supramolecular complexes that operate in aqueous solution are rare (10)(11)(12)(13)(14). While working on molecular recognition of imide functions by zinc(II) complexes of 12-membered tetraamine [Zn 2ϩ -1,4,7,10-tetraazacyclododecane (cyclen)] in aqueous solution (15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28), we tested interaction of cyanuric acid (CA) containing C 3 -symmetric three-imide functions with a C 3 -symmetric trinuclear zinc(II)-cyclen, Tris(Zn 2ϩ -cyclen) 1 [Zn 3 L 1 ; L 1 ϭ 1,3,5-Tris(1,4,7,10-tetraazacyclododecan-1-ylmethyl)benzene].…”

mentioning

confidence: 99%

See 1 more Smart Citation

New supramolecular trigonal prisms from zinc(II)– 1,4,7,10-tetraazacyclododecane (cyclen) complexes and trithiocyanurate in aqueous solution

Aoki

Zulkefeli

Shiro

et al. 2002

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

View full text Add to dashboard Cite

The multiple bonding between multinuclear zinc(II)-1,4,7,10-tetraazacyclododecane (cyclen, a 12-membered tetraamine) complexes and multidentate ligands is an effective method for constructing supramolecular complexes having well defined and distinct structures in aqueous solution. Herein we present examples of supramolecular D 3h prisms formed by self-assembly of linearly dimeric or trimeric zinc(II)-cyclen complexes with a potentially trianionic C 3 subunit trithiocyanuric acid (TCA 3؊ ), wherein Zn 2؉ OS ؊ or Zn 2؉ ON ؊ coordination bonds and hydrogen bonds are responsible for stability of the multicomponent architectures in aqueous solution at neutral pH.A rtificial supramolecular hosts with stable and well defined structures formed by spontaneous self-assembly of molecular building blocks in organic solvents have shown great potential for inclusion phenomena, molecular recognition, or catalysis (1-12). However, supramolecular complexes that operate in aqueous solution are rare (10)(11)(12)(13)(14). While working on molecular recognition of imide functions by zinc(II) complexes of 12-membered tetraamine [Zn 2ϩ -1,4,7,10-tetraazacyclododecane (cyclen)] in aqueous solution (15-28), we tested interaction of cyanuric acid (CA) containing C 3 -symmetric three-imide functions with a C 3 -symmetric trinuclear zinc(II)-cyclen, Tris(Zn 2ϩ -cyclen) 1 [Zn 3 L 1 ; L 1 ϭ 1,3,5-Tris(1,4,7,10-tetraazacyclododecan-1-ylmethyl)benzene]. We have discovered quantitative formation of a 2:3 1-dianionic CA (CA 2Ϫ ) complex at neutral pH that is represented schematically as a trigonal prism 2 ( Fig. 1; ref. 29). More interestingly, we accidentally isolated a 4:4 assembly [(Zn 3 L 1 ) 4 -(CA 3Ϫ ) 4 ] from basic aqueous solution. The x-ray crystal structure showed four sets of completely deprotonated CA (CA 3Ϫ ) binding to three Zn 2ϩ -cyclen units from three different Zn 3 L 1 at each N Ϫ rim (29). Its outer shape may be viewed as a cuboctahedron 3a with 12 vertices occupied by Zn 2ϩ and its inner shell as a truncated tetrahedron 4a. It was unfortunate, however, to find that this 4:4 cuboctahedral complex collapsed in neutral H 2 O, possibly because of the extremely high pK a value of the third imide proton of CA. More recently (30), this problem was overcome by replacing CA for TCA, the thioimide functions of which possess lower pK a values [5.12 (pK 1 ), 8.24 (pK 2 ), and 11.69 (pK 3 )] than those of CA [6.85 (pK 1 ), 10.91 (pK 2 ), and Ͼ12 (pK 3 )]. As anticipated, TCA acted as a tridentate donor for three Zn 3 L 1 at neutral pH to yield a similar type of the 4:4 self-assembling supercomplex 3b, in which the deprotonated TCA 3Ϫ in an aromatic 1,3,5-triazine bound to 1 through Zn 2ϩ OS Ϫ (exocyclic) coordination bonds, and thus the 4:4 assembly is a chiral, twisted cuboctahedron. More interestingly, 3b [(Zn 3 L 1 ) 4 -(TCA 3Ϫ ) 4 ] encapsulates various sizematched and hydrophobic guest molecules such as adamantane in its inner cavity, which is represented as a twisted, truncated tetrahedron 4b. Thus, we discovered an approach to de...

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

New supramolecular trigonal prisms from zinc(II)– 1,4,7,10-tetraazacyclododecane (cyclen) complexes and trithiocyanurate in aqueous solution

Aoki

Zulkefeli

Shiro

et al. 2002

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

View full text Add to dashboard Cite

show abstract

“…T he design of molecular containers represents an important component of nanotechnology and has attracted intense interest from synthetic chemists (1)(2)(3)(4). Research on molecular containers can realistically be expected to provide highly selective sensors, sorters, and catalysts for numerous applications.…”

mentioning

confidence: 99%

Systematic assembly of the double molecular boxes: {Cs⊂[CpCo(CN)₃]₄[Cp*Ru]₃} as a tridentate ligand

Contakes

Kuhlman

Ramesh

et al. 2002

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

View full text Add to dashboard Cite

T he design of molecular containers represents an important component of nanotechnology and has attracted intense interest from synthetic chemists (1-4). Research on molecular containers can realistically be expected to provide highly selective sensors, sorters, and catalysts for numerous applications. A significant challenge in this area is the development of containers that are stereochemically rigid, because rigidity is the basis of sterically governed selectivity. Rigidity, however, is incompatible with much of organic chemistry, and this dichotomy is problematic because organic (and organometallic) chemistry provides the most versatile construction tools for the synthesis of molecular containers. In this contribution, we address this dichotomy, i.e., the incorporation of organic motifs into rigid frameworks. Our approach involves a hybridization of organometallic chemistry and well established precedents in the chemistry of metal cyanides.Cyanometallates are metal complexes with the general formula L l M m (CN) n . The most important cyanometallate is Prussian blue (PB), an inorganic polymer with the formula Fe 7 (CN) 18 (H 2 O) x (x ϳ 15) (5). The synthesis of this useful solid arises from the condensation of [Fe(CN) 6 ] 4Ϫ and Fe(III) salts (Eq. 1).The structure of PB may be roughly described as interconnected cubic cage subunits with Fe vertices linked by cyanide. The PB structure is in fact complicated because the otherwise idealized cubic framework is interrupted by vacancies at the metal positions, these vacancies being occupied by water molecules (6). A building block approach is inherent in Eq. 1, i.e., the use of preassembled [Fe(CN) In recent years we have developed families of molecular cyanometallate ensembles that are synthesized analogously to PB, except that our molecular building blocks are tricyanometallates wherein the three cyanide ligands are mutually cis. Half of the coordination sphere of these tricyanometallates is occupied by a strongly coordinating nondisplaceable coligand. The face-capping coligand inhibits the formation of polymers by minimizing crosslinking but still promotes the formation of three-dimensional structures, which resemble subunits of PB. Particularly effective as face-capping ligands are cyclopentadienyl, C 5 H 5 (Cp), and its pentamethyl analogue, C 5 Me 5 (pentamethylcyclopentadienyl, Cp*). In a proof of concept experiment, we showed that [CpCo (CN

show abstract

“…For the synthetic chemist, self-assembly represents a powerful synthetic methodology in the creation of large, discrete, ordered structures from relatively simple synthons. A number of such synthons have been developed, particularly organic hydrogenbond donors and acceptors (4,5) or metal (M) and ligand (L) components (6)(7)(8)(9)(10).…”

mentioning

confidence: 99%

Supramolecular assembly dynamics

Davis

Yeh²,

Raymond³

2002

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

226

132

View full text Add to dashboard Cite

Molecular paneling via coordination

Cited by 898 publications

References 40 publications

New supramolecular trigonal prisms from zinc(II)– 1,4,7,10-tetraazacyclododecane (cyclen) complexes and trithiocyanurate in aqueous solution

New supramolecular trigonal prisms from zinc(II)– 1,4,7,10-tetraazacyclododecane (cyclen) complexes and trithiocyanurate in aqueous solution

Systematic assembly of the double molecular boxes: {Cs⊂[CpCo(CN)₃]₄[Cp*Ru]₃} as a tridentate ligand

Supramolecular assembly dynamics

Contact Info

Product

Resources

About

Molecular paneling via coordination

Cited by 898 publications

References 40 publications

New supramolecular trigonal prisms from zinc(II)– 1,4,7,10-tetraazacyclododecane (cyclen) complexes and trithiocyanurate in aqueous solution

New supramolecular trigonal prisms from zinc(II)– 1,4,7,10-tetraazacyclododecane (cyclen) complexes and trithiocyanurate in aqueous solution

Systematic assembly of the double molecular boxes: {Cs⊂[CpCo(CN)3]4[Cp*Ru]3} as a tridentate ligand

Supramolecular assembly dynamics

Contact Info

Product

Resources

About

Systematic assembly of the double molecular boxes: {Cs⊂[CpCo(CN)₃]₄[Cp*Ru]₃} as a tridentate ligand