A Metal‐Based Trisimidazolium Cage That Provides Six CH Hydrogen‐Bond‐Donor Fragments and Includes Anions

Amendola, Valeria; Boiocchi, Massimo; Colasson, Benoît; Fabbrizzi, Luigi; Rodriguez‐Douton, Maria Jesus; Ugozzoli, Franco

doi:10.1002/anie.200602598

Cited by 115 publications

(59 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…[1] Amongt he various types of these receptors,i midazoliumbased supramolecules have been extensively investigated [1a, 2] since the pioneering works by Sato et al, [3] Alcalde et al, [4] Kim et al, [5] and Fabbrizzi et al [6] Due to their cationic nature,i ti s now well accepted that the recognition of anions by this type of receptors is dominatedb yacombination of electrostatic interactions and hydrogen bonding[ (CÀH) + ··· A À ]. [1] Amongt he various types of these receptors,i midazoliumbased supramolecules have been extensively investigated [1a, 2] since the pioneering works by Sato et al, [3] Alcalde et al, [4] Kim et al, [5] and Fabbrizzi et al [6] Due to their cationic nature,i ti s now well accepted that the recognition of anions by this type of receptors is dominatedb yacombination of electrostatic interactions and hydrogen bonding[ (CÀH) + ··· A À ].…”

Section: Introductionmentioning

confidence: 99%

Rim, Side Arms, and Cavity: Three Sites for the Recognition of Anions by Tetraazolium Resorcinarene Cavitands

Ruiz-Botella

Vidossich

Ujaque

et al. 2016

Chemistry A European J

View full text Add to dashboard Cite

Two tetrabenzoimidazolium-resorcinarene cavitands were prepared and used for the recognition of chloride, bromide, iodide, cyanide, nitrate, perchlorate, hexanoate, benzenesulfonate, and p-toluenesulfonate. Binding affinities of the two cavitands were determined by H NMR titration and computational analysis. The observed spectral changes were related to specific interaction sites, which were supported by the computational studies. In the case of the C2-H tetrabenzoimidazolium-resorcinarene, the recognition region of the inorganic anions and hexanoate was located at the rim of the cavitand, although chloride and bromide also interacted with the aromatic C-H bonds located between adjacent arms of the cavitand. By contrast, the recognition of the two anions with an aromatic ring (benzenesulfonate and p-toluenesulfonate) results from encapsulation of the aromatic part of the anions inside the hydrophobic cavity of the host. In the case of the C2-Me tetrabenzoimizazolium-resorcinarene receptor, the ability of the molecule to bind all inorganic anions and hexanoate was suppressed, but the receptor maintained its ability to strongly bind benzenesulfonate and p-toluenesulfonate. This is interpreted in terms of suppression of the ability of the cavitand to form hydrogen bonds at the rim of the molecule due to replacement of the C2-H proton by a methyl group, while the hydrophobic pocket of the molecule maintains its binding abilities.

show abstract

Section: Introductionmentioning

confidence: 99%

Rim, Side Arms, and Cavity: Three Sites for the Recognition of Anions by Tetraazolium Resorcinarene Cavitands

Ruiz-Botella

Vidossich

Ujaque

et al. 2016

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…[1] However,i nvestigations of these compounds have been hindered by al ack of efficient preparative methods for their synthesis.O nly very few examples of rather small trisimidazolium cage compounds linked by two 1,3,5-trialkylbenzene caps have been reported thus far. [2,3] Following the first reports on anion recognition and binding by atrisimidazolium cage compound [4] and various macrocyclic polyazolium compounds, [5] as trong interest in the molecular recognition properties of polyazolium-functionalized cyclophanes developed, and this topic has been reviewed. [6][7][8][9] Most of the reported polyimidazolium structures are macrocycles that feature two or four imidazolium units.…”

mentioning

confidence: 99%

Template Synthesis of Three‐Dimensional Hexakisimidazolium Cages

et al. 2018

View full text Add to dashboard Cite

A procedure for the synthesis of three-dimensional hexakisimidazolium cage compounds has been developed. The reaction of the trigonal trisimidazolium salts H L(PF ) , decorated with three N-olefinic pendants, and silver oxide yielded trinuclear trisilver(I) hexacarbene molecular cylinders of the type [Ag L ] with the olefinic pendants from the two different tricarbene ligands arranged in three pairs. Subsequent UV irradiation gave three cyclobutane links between the two tris-NHC ligands in three [2+2] cycloaddition reactions, thereby generating a three-dimensional hexakis-NHC ligand. Removal of the metal ions resulted in the formation of three-dimensional hexakisimidazolium cages with a large internal cavity.

show abstract

“…The negatively charged moiety of N or O can provide hydrogen bonds with cations. On the other hand, recently, the (C-H) + ···anion ionic H-bond by the imidazolium group has been explored to synthesize positively charged receptors27282930313233. Mostly, the reported imidazolium-based receptors have one to four imidazolium moieties in the form of tweezers, dipodal, tripodal and other open forms.…”

mentioning

confidence: 99%

Calix[n]imidazolium as a new class of positively charged homo-calix compounds

et al. 2013

View full text Add to dashboard Cite

Macrocycles based on neutral calixarenes and calixpyrroles have been extensively explored for ion binding, molecular assembly and related applications. Given that only these two types of calix compounds and their analogs are available, the introduction of new forms of widely usable calix macrocycles is an outstanding challenge. Here we report the quadruply/quintuply charged imidazole-based homo-calix compounds, calix[4/5]imidazolium. The noncovalent (C-H)+/π+-anion interactions of the imidazolium rings with anions inside and outside the cone are the stabilizing factors for crystal packing, resulting in self-assembled arrays of cone-shaped calix-imidazolium molecules. Calix[4]imidazolium senses fluoride selectively even in aqueous solutions. Calix[5]imidazolium recognizes neutral fullerenes through π+–π interactions and makes them soluble in water, which could be useful in fullerene chemistry. Not only derivatization and ring expansion of calix[n]imidazolium, but also their utilization in ionic liquids, carbene chemistry and nanographite/graphene exfoliation could be exploited.

show abstract

A Metal‐Based Trisimidazolium Cage That Provides Six CH Hydrogen‐Bond‐Donor Fragments and Includes Anions

Cited by 115 publications

References 17 publications

Rim, Side Arms, and Cavity: Three Sites for the Recognition of Anions by Tetraazolium Resorcinarene Cavitands

Rim, Side Arms, and Cavity: Three Sites for the Recognition of Anions by Tetraazolium Resorcinarene Cavitands

Template Synthesis of Three‐Dimensional Hexakisimidazolium Cages

Calix[n]imidazolium as a new class of positively charged homo-calix compounds

Contact Info

Product

Resources

About