Assemblies In Solid State Research Articles

Synthesis, properties, and solid-state assemblies of β-alkyl-substituted dipyrrolyldiketone BF 2 complexes

In this paper, the synthesis and solid-state structures of β-alkyl-substituted dipyrrolyldiketone BF 2 complexes are discussed; these complexes can function as π-conjugated acyclic anion receptors (“molecular flippers”) and are potential building subunits of anion-responsive π-conjugated oligomers or polymers. Modes of the solid-state assemblies in these complexes determined by performing single-crystal X-ray analysis are found to depend on the lengths of the alkyl chains at the β-positions. A β-methyl-substituted receptor has a highly planar structure, which efficiently forms stacking assemblies in the core π-plane in the solid state, while a β-ethyl-substituted receptor shows no stacking assemblies due to the presence of bulky ethyl moieties, which form only dimeric structures by hydrogen bonding. β-Alkyl-substituted anion receptors can be used not only as monomer units of stimuli-responsive polymeric macromolecules but also as components of solid-state electronic materials.

Alkoxy-substituted Derivatives of π-Conjugated Acyclic Anion Receptors: Effects of Substituted Positions

Abstract The synthesis, solid-state assemblies, and anion binding affinities of π-conjugated acyclic anion receptors with alkoxyphenyl substituents are discussed. The position of the alkoxy moiety is essential to determining not only the electronic state but also the anion binding affinity.

Dimolybdenum Bis-2,4,6-triisopropyl-benzoate Bis-4-isonicotinate: A Redox Active Analogue of 4,4′-Bipyridine with Ambivalent Properties

The reaction between Mo2(TiPB)4 and 4-iso-nicotinic acid (2 equiv) in ethanol leads to the formation of trans-Mo2(TiPB)2(nic)2, I, where TiPB = 2,4,6-triisopropylbenzoate and nic = 4-isonicotinate. The molecular structures of I and I x 2DMSO were determined in the solid state by a single-crystal X-ray study, and its electronic structure was determined by DFT calculations on a model compound, where formate ligands were substituted for the bulky TiPB. The physicochemical properties of I are reported, and its potential as a redox active building block, a quasi-metalloorganic analogue of 4,4'-bipyridine, is described in the synthesis of molecular and solid-state assemblies. The molecular structure of I in the solid state consists of a 3-dimensional network in which each unit of Mo2(TiPB)2(nic)2 acts as a donor and acceptor via N to Mo coordination. In the structure of I x 2DMSO, the DMSO ligands coordinate axially with the Mo-Mo bond via oxygen. The reaction between I and Rh2(O2CMe)4 is shown to give a 1-D polymeric chain in the solid state: [{Rh2(O2CMe)4}{Mo2(TiPB)2(nic)2}] infinity, II. A similar structure was found for the product involving Rh2(O2CCMe3)4. Evidence is also reported for the formation of [(1,5-COD)MePt]2[mu-Mo2(TiPB)2(nic)2](PF6)2, III, and [(1,5-COD)Pt(mu-I)(PF6)2]n.

Synthesis and structural characterization of 2,5-dihalo-3,4-dinitrothiophenes

Using new nitration protocols, we have been able to efficiently dinitrate 2,5-dihalothiophenes with yields of ∼80–95%. The resulting products 2,5-dibromo-3,4-dinitrothiophene (1), 2,5-dichloro-3,4-dinitrothiophene (2), 2-bromo-5-chloro-3,4-dinitrothiophene (3), as well as the analogous 2-bromo-3,4-dinitrothiophene (4), all crystallize easily allowing their characterization via X-ray crystallography. Crystallization of 1 occurs in the monoclinic space group C2/c with a = 14.547(3) A, b = 7.3534(15) A, c = 10.775(2) A, β = 128.89(3)°, and Z = 4. Crystallization of 2 occurs in the tetragonal space group I-42d with a = 9.9398(14) A, b = 9.9398(14) A, c = 16.866(3) A, and Z = 8. Crystallization of 3 occurs as a pseudo-merohedral twin in the triclinic space group P-1 with a = 7.340(5) A, b = 8.094(5) A, c = 9.112(5) A, α = 82.059(5)°, β = 66.232(5)°, γ = 63.021(5)°, and Z = 2. Crystallization of 4 occurs in the triclinic space group P-1 with a = 7.1787(14) A, b = 7.4092(15) A, c = 8.3151(17) A, α = 101.67(3)°, β = 96.00(3)°, γ = 116.13(3)°, and Z = 2. The structures of all compounds exhibit the formation of interesting solid-state assemblies due to halogen-bonding interactions between the halogen and nitro groups.

Solid-state assemblies from pyridine-2,6-dicarboxylates: “changing the instruction set through hydration”

A novel dihydrate structure of pyridine-2,6-dicarboxylic (dipicolinic) acid is reported, found to demonstrate a different solid-state architecture to that of the previously published monohydrate crystal. In addition, we report the crystal structure of a monohydrate of 4-chloro pyridine-2,6-dicarboxylic acid, which is also compared to the known dipicolinic acid monohydrate.

Solid-state assemblies and optical properties of conjugated oligomers combining fluorene and thiophene units

Two conjugated oligomers, representing elementary segments of fluorene–thiophene copolymers, are compared in terms of the microscopic morphology and the optical properties of thin deposits. The atomic force microscopy morphological data and the solid-state absorption and emission spectra are interpreted in terms of the assembly of the conjugated molecules. The compound with a terthiophene central unit and fluorene end-groups shows well-defined monolayer-by-monolayer assembly into micrometer-long stripe-like structures, with a crystalline herringbone-type organization within the monolayers. Polarized confocal microscopy indicates a strong orientation of the crystalline domains within the stripes. In contrast, the compound with a terfluorene central unit and thiophene end groups forms no textured aggregates and the optical spectra in the solid-state are very similar to those recorded in solution, suggesting that the molecules interact only weakly in the solid. The difference in behaviour between the two compounds most probably originates from their different capability to form densely-packed assemblies of interacting π-systems.

Synthesis, coordination and catalytic use of 1-(diphenylphosphino)-1′-carbamoylferrocenes with pyridyl-containing N-substituents

Ferrocene phosphinocarboxamides, 1-(diphenylphosphino)-1'-{N-[(2-pyridyl)methyl]carbamoyl}ferrocene (1) and 1-(diphenylphosphino)-1'-{N-[2-(2-pyridyl)ethyl]carbamoyl}ferrocene (2) were prepared from 1-(diphenylphosphino)-1'-ferrocenecarboxylic acid and studied as ligands for palladium. Starting with [PdCl2(cod)], the reactions at a 2 : 1 ligand-to-metal ratio gave uniformly the bis-phosphine complexes [PdCl2(L-kappaP)2] (3, L = 1; 4, L = 2) whereas those performed at a 1 : 1 ratio yielded distinct products: [PdCl2(1-kappa(2)P,N)] (5) with 1 coordinating as a trans-spanning P,N-donor, and the symmetric, P,N-bridged dimer [(micro-2-N,P)2{PdCl2}2] (6), respectively. The crystal structures of 1, 2, 4.4CHCl3, 5.AcOH, and 6.8CHCl3 as determined by X-ray diffraction showed the compounds to form well defined solid-state assemblies through hydrogen bonds. Testing of the phosphinocarboxamides in the palladium-catalysed Suzuki cross-coupling reaction revealed 1 and 2, combined with Pd(OAc)2 to form efficient catalysts for the reactions of aryl bromides while aryl chlorides coupled only when activated with electron-withdrawing groups.

Role of Hydrogen-Bonded Interactions in the Crystal Packing of Phenylenediammonium Phosphomolybdates

Self-assembled synthesis of three new organic/inorganic hybrid solids (1−3) in the presence of isomeric phenylenediammonium ions (p-, m-, and o-) demonstrates the role of nonbonding interactions in the construction of phosphomolybdate-based solid-state assemblies. In 1, crystal packing is dominated by two kinds of supramolecular assemblies: an unusual pentadecameric water cluster linked through p-phenylenediammonium (ppda) cations and a hydrogen-bonded assembly of a ppda cation with four phosphomolybdate anions. In 2, a pair of m-phenylenediammonium (mpda) cations linked through π···π interactions envelops a phosphomolybdate anion from either side through hydrogen bonding mediated by water molecules forming butterfly-like supramolecular motifs. In 3, a new kind of O−W−O−W (organic−water) linker formed by alternate hydrogen bonding between o-phenylenediammonium (opda) and water molecules; such motifs are well decorated around a pentamolybdate cluster anion leading to the formation of the three-dimensional...

Shape-persistent macrocyclic aromatic tetrasulfonamides: Molecules with nanosized cavities and their nanotubular assemblies in solid state.

Alkoxy side-chain-flanked diarylsulfonamide serves as a reliable structural motif for constructing macrocyclic aromatic tetrasulfonamides. This 90 degrees structural motif is persistent both in solution and in the solid state, which allows the one-step formation of tetrasulfonamide macrocycles. These macrocycles adopt a cone-shaped conformation in solution and in the solid state. For each molecule, an interior cavity surrounded by the aromatic residues is formed. The cavity sizes of the macrocycles can be tuned by incorporating aromatic residues of proper sizes. Guest (solvent) molecules are found in the cavities and bound by side chains. In solution, 1H NMR shows that the cone conformations undergo rapid interconversion at room temperature. The alkoxy side chains are found to be indispensable for maintaining the cone conformation. In addition, these porous molecules self-assemble into hollow tubular structures in the solid state. A variety of host molecules and building blocks for constructing nanoporous solid-state structures can be expected from these molecules.

Solid-state tubular assemblies of thiolactones: synthesis and structural characterization

The synthesis of cyclic thiolactones, 2,5,8-trithiacyclododecane-1,9-dione ( 4 ), 2,5,8,14,17,20-hexathiacyclotetracosane-1,9,13,21-tetraone ( 5 ), 2,5,8-trithiacyclotetradecane-1,9-dione ( 6 ) and 2,5,8,16,19,22-hexathiacyclooctacosane-1,9,15,23-tetraone ( 7 ) was achieved by tin-template reaction of 2,2-dibutyl-2-stanna-1,3,6-trithiacyclooctane ( 1 ) with corresponding diacyl chlorides. The structures of 12-, 14-, 24- and 28-membered ring systems of 4 , 6 , 5 , and 7 , respectively, were investigated by X-ray structure analysis. These investigations revealed that, in the solid-state, thiolactones 4 and 7 form tubular assemblies. However, the crystal structure of 5 forms layered packing dominated by CH⋯O hydrogen bonds whereas 6 forms three-dimensional network via CH⋯O hydrogen bonds and van der Waals interactions.

Acid-base and counter ion dependent solid-state assembly of a ferrocene β-aminoalcohol and the corresponding ammonium salt

2-(Ferrocenylmethyl)amino-2-methylpropan-1-ol was synthesized and converted to the respective ammonium bromide ([ 1H]Br ≡ 2) and dihydrogenphosphate ([ 1H]H 2PO 4 ≡ 3). The solid-state structures of 1, 2 and the solvated salt 3 · 1/6Et 2O ( 3a) have been determined by X-ray diffraction. The solid-state assemblies of 1 and 2 are dominated by infinite ladder-like arrays interconnected by hydrogen bonds whereas the solid-state structure of 3a is built up from linear hydrogen-bonded dihydrogenphosphate chains, which are interlinked via hydrogen bonds to the cations [ 1H] + into a complicated three-dimensional network. Compound 1 and its interactions with Bu 4NBr and Bu 4NH 2PO 4 in solution were further studied by electrochemical methods and NMR titrations.

New Bulky Allyl Complexes of Lanthanide Metals: Role of Alkali-Metal Cations in Controlling Solid-State and Solution Assemblies in Precatalysts

The reaction of the bulky allyl anion [1,3-C3H3(SiMe3)2]- with SmI2(THF)2 gives the allyl-bridged dimer [Sm(C3H3(SiMe3)2)3{μ-K(THF)2}]2, the first structurally authenticated Sm(II) allyl complex. The compound is a highly effective single-component catalyst for the polymerization of methyl methacrylate and e-caprolactone.

Functionalized macrocyclic ligands for use in supramolecular chemistry.

The synthesis of three cross-conjugated macrocycles bearing pyridine functionality is described. The ability of two of these molecules, 5a and 5c, to behave as 4,4'-bipyridine mimics in self-assembly reactions is demonstrated by axial coordination to a metalloporphyrin. The directed coordinative ability of the pyridine rings ensures predictable self-assembly into well-ordered nanoscale systems, both in solution and the solid state. 1H, 13C, and HMQC NMR spectroscopic experiments and ESI MS have been used to characterize the supramolecular complexes in solution. X-ray crystallographic analysis of solid-state assemblies 7a and 7c provides insight into the scope and flexibility of these macrocyclic ligands as supramolecular building blocks. UV-vis and fluorescence spectroscopies provide a description of their electronic characteristics.

Packaging of integrated solid-state power assembly cells: a thermomechanics-based approach

The design of integrated solid-state power assemblies presents unique challenges originating from the high current, voltage, and temperature levels at which they operate. Specifically, they are subject to high levels of internal mechanical stress owing to the dissimilar materials from which they are fabricated coupled with the higher temperatures and currents that develop within the modules during their operation. However, as future demands grow for compact power assemblies with ever-increasing controlled-power density coupled with low cost and straightforward manufacturability, the necessity for a predictive capability for their reliability is greater than ever. Surprisingly, despite the lack of a widely accepted methodology for such designs, much of the basic knowledge is in place. Therefore, the goal of this article is to summarize the main modes of failure in power assemblies, the corresponding material degradation mechanisms and driving forces, and the material properties that are required to help stimulate further developments in this area. A vital component of the approach presented here is to base the understanding on a rigorous knowledge of the physics involved in failure.

Molecular assembly in an inclusion crystal of tris(2-benzimidazylmethyl)amine with 4-nitrobenzoic acid

A 1:2 inclusion compound of tris(2-benzimidazylmethyl)amine with 4-nitrobenzoic acid [(C24H21N7) · (C7H5NO2)2] has been prepared and the molecular assembly in solid state has been determined by X-ray crystal structural analysis. The crystal structure (C 2/c, a = 25.488(5), b = 13.304(3), c = 21.479(4) A, β = 93.35 (3)°, Z = 8, R = 0.065) consists of discrete dimeric inclusion compounds joined together by N(5)...N(6) intermolecular hydrogen bonds between pairs of centrosymmetrically related benzimidazole rings of the hosts. There are two types of guest molecules in the crystal, one is incorporated within the cavity of the host via three intramolecular N—H···O hydrogen bonds while the other is situated outside the cavity and connected with the host through one O—H···N hydrogen bond. The π–π stacking interactions between guests and benzimidazole rings result in one-dimensional columns. The aromatic face–face interactions between neighbouring columns facilitate the assembly of those columns into two-dimensional layers.

Perspectives on Solid-State Host-Guest Assemblies

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPerspectives on Solid-State Host-Guest AssembliesV. Ramamurthy and D. F. EatonCite this: Chem. Mater. 1994, 6, 8, 1128–1136Publication Date (Print):August 1, 1994Publication History Published online1 May 2002Published inissue 1 August 1994https://doi.org/10.1021/cm00044a011RIGHTS & PERMISSIONSArticle Views343Altmetric-Citations93LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (996 KB) Get e-Alerts Get e-Alerts