ChemInform Abstract: Probing the Self-Assembly Mechanism of Lanthanide-Containing Sandwich-Type Silicotungstates [{Ln(H2O)n}2{Mn4(B-α-SiW9O34)2(H2O)2}]6-Using Time-Resolved Mass Spectrometry and X-Ray Crystallography.

The self assembly of Ag[PF6], bis(diphenylphosphino)ethyne and a bpy or tpy ligand was studied in solution using 31P–109Ag HSQC spectroscopy and by X-ray crystallography.

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Self-Assembly of a Charge-Neutral Molecular Square

Australian Journal of Chemistry ◽

10.1071/ch03319 ◽

2004 ◽

Vol 57 (5) ◽

pp. 409 ◽

Cited By ~ 11

Author(s):

Mohammad Akbar Ali ◽

Paul V. Bernhardt ◽

Chong Lee Kiem ◽

Aminul Huq Mirza

Keyword(s):

Molecular Weight ◽

Solid State ◽

Self Assembly ◽

1H Nmr Spectroscopy ◽

The Self ◽

State Structure ◽

X Ray ◽

X Ray Crystallography ◽

A Charge ◽

Molecular Square

Complexation of cadmium(II) by the ditopic (bis-tridentate) thiocarbazone ligand 1,5-bis(6-methyl-2-pyridyl- methylene)thiocarbonohydrazide, H2L1, results in the self-assembly of a charge-neutral 2 × 2 molecular grid, [Cd4(L1)4], comprising four metals and four ligands in an interlocked cyclic array. The solid-state structure of this tetramer has been established by X-ray crystallography and in solution by 1H NMR spectroscopy. The presence of lower molecular weight oligomers was identified by both NMR and ESI-MS.

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Synthesis and aggregation properties of boron-dipyrromethene dyes conjugated with guanine units

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s108842461850089x ◽

2018 ◽

Vol 22 (09n10) ◽

pp. 944-952 ◽

Cited By ~ 2

Author(s):

Fen Li ◽

Yongjie Zhang ◽

Lina Zhou ◽

Xin Zhang ◽

Zhijian Chen

Keyword(s):

Self Assembly ◽

Solvent Polarity ◽

The Self ◽

X Ray ◽

X Ray Crystallography ◽

H Nmr ◽

Nmr Study ◽

Vis Spectroscopy ◽

G Quadruplex ◽

Boron Dipyrromethene

Two boron-dipyrromethene dyes bearing a conjugated guanine unit (G-BODIPYs) 1 and 2 were synthesized and fully characterized. The self-assembly properties of these dyes were investigated by X-ray crystallography, [Formula: see text]H NMR and UV-vis spectroscopy. As revealed by X-ray crystal structure studies, G-BODIPY 1 self-assembled into ribbon-like structures due to the intermolecular hydrogen bonding and [Formula: see text]–[Formula: see text] stacking interaction. Concentration-dependent [Formula: see text]H NMR experiments confirmed the formation of hydrogen bonds of the guanine units in solution for both dye 1 and 2. In the presence of K[Formula: see text], the characteristic signals for the formation of cyclic G-quadruplex structures were observed in the [Formula: see text]H NMR study. Aggregation of G-BODIPY dyes was further monitored by UV-vis absorption spectroscopy by varying the solvent polarity and temperature. H-type aggregates of dye 1, which was characterized by a new hypsochromically shifted absorption band with [Formula: see text] 461 nm, was obtained. In the presence of K[Formula: see text], the enhancement of stability was observed for the H-aggregates of dye 1.

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Self-assembly of metallosupramolecular rhombi from chiral concave 9,9’-spirobifluorene-derived bis(pyridine) ligands

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.10.40 ◽

2014 ◽

Vol 10 ◽

pp. 432-441 ◽

Cited By ~ 27

Author(s):

Rainer Hovorka ◽

Sophie Hytteballe ◽

Torsten Piehler ◽

Georg Meyer-Eppler ◽

Filip Topić ◽

...

Keyword(s):

Mass Spectrometry ◽

Nmr Spectroscopy ◽

Single Crystal ◽

Self Assembly ◽

The Self ◽

Assembly Process ◽

X Ray Diffraction ◽

X Ray ◽

Pyridine Ligands ◽

Racemic Form

Two new 9,9’-spirobifluorene-based bis(4-pyridines) were synthesised in enantiopure and one also in racemic form. These ligands act as concave templates and form metallosupramolecular [(dppp)2M2L2] rhombi with cis-protected [(dppp)Pd]2+ and [(dppp)Pt]2+ ions. The self-assembly process of the racemic ligand preferably occurs in a narcissistic self-recognising manner. Hence, a mixture of all three possible stereoisomers [(dppp)2M2{(R)-L}2](OTf)4, [(dppp)2M2{(S)-L}2](OTf)4, and [(dppp)2M2{(R)-L}{(S)-L}](OTf)4 was obtained in an approximate 1.5:1.5:1 ratio which corresponds to an amplification of the homochiral assemblies by a factor of approximately three as evidenced by NMR spectroscopy and mass spectrometry. The racemic homochiral assemblies could also be characterised by single crystal X-ray diffraction.

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Flexibility in the Self-Assembly of Silver Complexes: Coordination Polymers from Multi-Armed Pyridylmethyleneoxy Ligands

Australian Journal of Chemistry ◽

10.1071/ch12464 ◽

2013 ◽

Vol 66 (4) ◽

pp. 443 ◽

Cited By ~ 7

Author(s):

Peter J. Steel ◽

Christopher M. Fitchett

Keyword(s):

Coordination Polymers ◽

Self Assembly ◽

Pyridine Ring ◽

Relative Orientation ◽

The Self ◽

Silver Complexes ◽

X Ray ◽

Precise Nature ◽

X Ray Crystallography

The syntheses of new silver complexes of five isomeric bis(pyridylmethyleneoxy)benzenes, differing in the position of substitution on the benzene and pyridine rings, and three isomeric 1,3,5-tris(pyridylmethyleneoxy)benzenes, differing in the position of substitution on the pyridine ring, are described. The structures of six of these complexes were characterised using X-ray crystallography, showing the formation of coordination polymers for 3-pyridyl- and 4-pyridyl-armed ligands and discrete complexes for 2-pyridyl-armed ligands. The precise nature of the structure was further determined by the relative orientation of the pyridine rings in each case.

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Controlling the Shape and Chirality of an Eight-crossing Molecular Knot

10.26434/chemrxiv.13123178.v1 ◽

2020 ◽

Author(s):

John P. Carpenter ◽

Charlie McTernan ◽

Jake L. Greenfield ◽

Roy Lavendomme ◽

Tanya K. Ronson ◽

...

Keyword(s):

Mass Spectrometry ◽

Self Assembly ◽

Metal Salt ◽

Molecular Machines ◽

One Pot ◽

X Ray ◽

X Ray Crystallography ◽

And Topology ◽

Simple Pair ◽

And Control

The knotting of biomolecules impacts their function, and enables them to carry out new tasks. Likewise, complex topologies underpin the operation of many synthetic molecular machines. The ability to generate and control more complex knotted architectures is essential to endow these machines with more advanced functions. Here we report the synthesis of a molecular knot with eight crossing points, consisting of a single organic loop woven about six templating metal centres, via one-pot self-assembly from a simple pair of dialdehyde and diamine subcomponents and a single metal salt. The structure and topology of the knot were established by NMR spectroscopy, mass spectrometry and X-ray crystallography. Upon demetallation, the purely organic strand relaxes into a symmetric conformation, whilst retaining the topology of the original knot. This knot is topologically chiral, and may be synthesised diastereoselectively through the use of an enantiopure diamine building block.

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Controlling the Shape and Chirality of an Eight-crossing Molecular Knot

10.26434/chemrxiv.13123178 ◽

2020 ◽

Author(s):

John P. Carpenter ◽

Charlie McTernan ◽

Jake L. Greenfield ◽

Roy Lavendomme ◽

Tanya K. Ronson ◽

...

Keyword(s):

Mass Spectrometry ◽

Self Assembly ◽

Metal Salt ◽

Molecular Machines ◽

One Pot ◽

X Ray ◽

X Ray Crystallography ◽

And Topology ◽

Simple Pair ◽

And Control

The knotting of biomolecules impacts their function, and enables them to carry out new tasks. Likewise, complex topologies underpin the operation of many synthetic molecular machines. The ability to generate and control more complex knotted architectures is essential to endow these machines with more advanced functions. Here we report the synthesis of a molecular knot with eight crossing points, consisting of a single organic loop woven about six templating metal centres, via one-pot self-assembly from a simple pair of dialdehyde and diamine subcomponents and a single metal salt. The structure and topology of the knot were established by NMR spectroscopy, mass spectrometry and X-ray crystallography. Upon demetallation, the purely organic strand relaxes into a symmetric conformation, whilst retaining the topology of the original knot. This knot is topologically chiral, and may be synthesised diastereoselectively through the use of an enantiopure diamine building block.

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In situ Time-Resolved Small-Angle X-ray Scattering Reveals the Formation Kinetics of Polyelectrolyte Complex Micelles

10.26434/chemrxiv.9876395.v1 ◽

2019 ◽

Author(s):

Hao Wu ◽

Jeffrey Ting ◽

Siqi Meng ◽

Matthew Tirrell

Keyword(s):

Small Angle ◽

Self Assembly ◽

Electrostatic Interactions ◽

Polyelectrolyte Complex ◽

Time Resolved ◽

X Ray ◽

X Ray Scattering ◽

Kinetics Of ◽

Ray Scattering

We have directly observed the in situ self-assembly kinetics of polyelectrolyte complex (PEC) micelles by synchrotron time-resolved small-angle X-ray scattering, equipped with a stopped-flow device that provides millisecond temporal resolution. This work has elucidated one general kinetic pathway for the process of PEC micelle formation, which provides useful physical insights for increasing our fundamental understanding of complexation and self-assembly dynamics driven by electrostatic interactions that occur on ultrafast timescales.

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