Synergistic effects of halogen bond and π–π interactions in thiophene-based building blocks

Two new aromatic pyrimidine-based derivatives designed specifically for halogen bond directed self-assembly are investigated through a combination of high-resolution Raman spectroscopy, X-ray crystallography, and computational quantum chemistry. The vibrational frequencies of these new molecular building blocks, pyrimidine capped with furan (PrmF) and thiophene (PrmT), are compared to those previously assigned for pyrimidine (Prm). The modifications affect only a select few of the normal modes of Prm, most noticeably its signature ring breathing mode, ν1. Structural analyses afforded by X-ray crystallography, and computed interaction energies from density functional theory computations indicate that, although weak hydrogen bonding (C–H···O or C–H···N interactions) is present in these pyrimidine-based solid-state co-crystals, halogen bonding and π-stacking interactions play more dominant roles in driving their molecular-assembly.

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Anion Templated Crystal Engineering of Halogen Bonding Tripodal Tris(halopyridinium) Compounds

10.26434/chemrxiv.11862900.v1 ◽

2020 ◽

Author(s):

Emer Foyle ◽

Nicholas White

Keyword(s):

Crystal Engineering ◽

Self Assembly ◽

Halogen Bond ◽

Halogen Bonding ◽

Halogen Bonds ◽

X Ray ◽

X Ray Crystallography ◽

H Nmr ◽

Structural Database ◽

Van Der Waals Radii

<div>In this work four new tripodal tris(halopyridinium) receptors containing potentially halogen</div><div>bonding groups were prepared. The ability of the receptors to bind anions in competitive</div><div>CD<sub>3</sub>CN/d<sub>6</sub>-DMSO was studied using <sup>1</sup>H NMR titration experiments, which revealed that the</div><div>receptors bind chloride anions more strongly than more basic acetate or other halide ions.</div><div>The solid state self–assembly of the tripodal receptors with halide anions was investigated by</div><div>X-ray crystallography. The nature of the structures was dependent on the choice of halide</div><div>anion, as well as the crystallisation solvent. Halogen bond lengths as short as 80% of the sum</div><div>of the van der Waals radii were observed, which is shorter than any halogen bonds involving</div><div>halopyridinium receptors in the Cambridge Structural Database.</div>

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Anion Templated Crystal Engineering of Halogen Bonding Tripodal Tris(halopyridinium) Compounds

10.26434/chemrxiv.11862900 ◽

2020 ◽

Author(s):

Emer Foyle ◽

Nicholas White

Keyword(s):

Crystal Engineering ◽

Self Assembly ◽

Halogen Bond ◽

Halogen Bonding ◽

Halogen Bonds ◽

X Ray ◽

X Ray Crystallography ◽

H Nmr ◽

Structural Database ◽

Van Der Waals Radii

<div>In this work four new tripodal tris(halopyridinium) receptors containing potentially halogen</div><div>bonding groups were prepared. The ability of the receptors to bind anions in competitive</div><div>CD<sub>3</sub>CN/d<sub>6</sub>-DMSO was studied using <sup>1</sup>H NMR titration experiments, which revealed that the</div><div>receptors bind chloride anions more strongly than more basic acetate or other halide ions.</div><div>The solid state self–assembly of the tripodal receptors with halide anions was investigated by</div><div>X-ray crystallography. The nature of the structures was dependent on the choice of halide</div><div>anion, as well as the crystallisation solvent. Halogen bond lengths as short as 80% of the sum</div><div>of the van der Waals radii were observed, which is shorter than any halogen bonds involving</div><div>halopyridinium receptors in the Cambridge Structural Database.</div>

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Cobaloximes as Building Blocks in Halogen-Bonded Cocrystals

Materials ◽

10.3390/ma13102370 ◽

2020 ◽

Vol 13 (10) ◽

pp. 2370

Author(s):

Nikola Bedeković ◽

Valentina Martinez ◽

Edi Topić ◽

Vladimir Stilinović ◽

Dominik Cinčić

Keyword(s):

Single Crystal ◽

Halogen Bond ◽

Halogen Bonding ◽

Building Blocks ◽

X Ray Diffraction ◽

X Ray ◽

Organic Halogen ◽

Metal Organic

In this work, we explore the halogen-bonded cocrystallization potential of cobaloxime complexes in the synthesis of cocrystals with perhalogenated benzenes. We demonstrate a strategy for synthesizing halogen-bonded metal–organic cocrystals by utilizing cobaloximes whose pendant bromide group and oxime oxygen enable halogen bonding. By combining three well-known halogen bond donor molecules differing in binding geometry and composition with three cobaloxime units, we obtained a total of four previously unreported cocrystals. Single crystal X-ray diffraction experiments showed that the majority of obtained cocrystals exhibited the formation of the targeted I···O and I···Br motives. These results illustrate the potential of cobaloximes as halogen bond acceptors and indicate that this type of halogen bond acceptors may offer a novel route to metal–organic halogen-bonded cocrystals.

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Crystalline assemblies of porphyrins with mixed bromophenyl and pyridyl meso-substituents and manifestation of supramolecular chirality induced by inter-porphyrin Br⋯N halogen bonds

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424611004166 ◽

2011 ◽

Vol 15 (11n12) ◽

pp. 1250-1257 ◽

Cited By ~ 13

Author(s):

Hatem M. Titi ◽

Anirban Karmakar ◽

Israel Goldberg

Keyword(s):

Self Assembly ◽

Halogen Bond ◽

Supramolecular Assembly ◽

Halogen Bonding ◽

Building Blocks ◽

Zinc Ion ◽

Halogen Bonds ◽

X Ray Diffraction ◽

Supramolecular Chirality ◽

Porphyrin Core

Four new crystalline solids based on the zinc-5,15-bis(4′-bromophenyl)-10,20- bis(4′-pyridyl)porphyrin ( Zn –DBDPyP) and zinc/copper-5,10,15-tris(4′-bromophenyl)-20-(4′-pyridyl)-porphyrin ( Zn/Cu –TBMPyP) platforms as building blocks, have been prepared and structurally analyzed by X-ray diffraction in order to examine whether the Br⋯N halogen bond can be effective in directing the supramolecular assembly of this functionalized porphyrins, in a similar way observed earlier for their iodophenyl-substituted analogs. The zinc ion in the porphyrin core was protected by an external ligand (pyridyl or methanol) to prevent its possible coordination to the pyridyl-porphyrin substituents. Neither the bis-pyridyl Zn (py)–DBDPyP scaffold nor the Zn(MeOH)/Cu –TBMPyP exhibited inter-porphyrin halogen bonding in their corresponding crystals. Only the layered self-assembly of the Zn (py)–TBMPyP building block was found to be uniquely directed by Br⋯N halogen bonds, as well as by Br⋯Br and Br⋯π interactions. This observation supports our notion that asymmetric functionalization of the tetraarylporphyrin scaffold, combined with directional interporphyrin interactions (as halogen bonding), represent a promising approach to supramolecular chirality.

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Synthesis of the [11]Cyclacene Framework by Repetitive Diels–Alder Cycloadditions

Molecules ◽

10.3390/molecules26103047 ◽

2021 ◽

Vol 26 (10) ◽

pp. 3047

Author(s):

John B. Bauer ◽

Fatima Diab ◽

Cäcilia Maichle-Mössmer ◽

Hartmut Schubert ◽

Holger F. Bettinger

Keyword(s):

Building Block ◽

Building Blocks ◽

Alder Reaction ◽

Diels Alder ◽

X Ray ◽

X Ray Crystallography ◽

Diels Alder Reaction ◽

Synthetic Intermediate

The Diels–Alder cycloaddition between bisdienes and bisdienophile incorporating the 7-oxa-bicyclo[2.2.1]heptane unit are well known to show high diastereoselectivity that can be exploited for the synthesis of molecular belts. The related bisdiene 5,6,7,8-tetramethylidene-2-bicyclo[2.2.2]octene is a valuable building block for the synthesis of photoprecursors for acenes, but it has not been employed for the synthesis of molecular belts. The present work investigates by computational means the Diels–Alder reaction between these bisdiene building blocks with syn-1,4,5,8-tetrahydro-1,4:5,8-diepoxyanthracene, which shows that the diastereoselectivity of the Diels–Alder reaction of the etheno-bridged bisdiene is lower than that of the epoxy-bridged bisdiene. The reaction of the etheno-bridged bisdiene and syn-1,4,5,8-tetrahydro-1,4:5,8-diepoxyanthracene in 2:1 ratio yields two diastereomers that differ in the orientation of the oxa and etheno bridges based on NMR and X-ray crystallography. The all-syn diastereomer can be transformed into a molecular belt by inter- and intramolecular Diels–Alder reactions with a bifunctional building block. The molecular belt could function as a synthetic intermediate en route to a [11]cyclacene photoprecursor.

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Synthesis and characterization of new tetra-substituted porphyrins with exo-donor carboxylic groups as building blocks for supramolecular architectures: Catalytic and structural studies of their metalated derivatives

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424610002641 ◽

2010 ◽

Vol 14 (09) ◽

pp. 804-814 ◽

Cited By ~ 4

Author(s):

Lucia Carlucci ◽

Gianfranco Ciani ◽

Simona Maggini ◽

Davide M. Proserpio ◽

Fabio Ragaini ◽

...

Keyword(s):

Building Blocks ◽

Supramolecular Organization ◽

Silver Complexes ◽

Structural Studies ◽

Polymeric Compound ◽

X Ray ◽

X Ray Crystallography ◽

Supramolecular Architectures ◽

Carboxylic Groups

We report herein the synthesis of the porphyrins 5,10,15,20-tetrakis(4-carboxybiphenyl)-porphyrin (H2TCBP) and 5,10,15,20-tetrakis(4-carboxy-2,6-dimethylbiphenyl)porphyrin (H2TCDMBP) bearing diphenyl units on meso-positions, and of their cobalt and silver derivatives. The silver complexes of H2TCDMBP and of H2TCPP ( H2TCPP = 5 ,10,15,20-tetrakis(4-carboxyphenyl)porphyrin) were investigated by X-ray crystallography and their supramolecular organization elucidated. Co(TCBP) was reacted with copper formate, yielding a polymeric compound that showed a catalytic activity in the benzylic amination of hydrocarbons using arylazide as aminating agent.

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The synergy of different solid-state techniques to elucidate the supramolecular assembly of two 1H-benzotriazole polymorphs

Physical Chemistry Chemical Physics ◽

10.1039/c9cp03209f ◽

2019 ◽

Vol 21 (36) ◽

pp. 19879-19889

Author(s):

María Mar Quesada-Moreno ◽

Juan Ramón Avilés-Moreno ◽

Juan Jesús López-González ◽

Fco. Javier Zúñiga ◽

Dolores Santa María ◽

...

Keyword(s):

Solid State ◽

Quantum Chemical Calculations ◽

Absolute Configuration ◽

Quantum Chemical ◽

Supramolecular Structure ◽

Supramolecular Assembly ◽

X Ray ◽

X Ray Crystallography ◽

The Absolute

4aα (chiral) and 4aβ (achiral) polymorphs of 1H-benzotriazole are studied by X-ray crystallography, SSNMR, IR, Raman, VCD, and quantum chemical calculations. The absolute configuration of the supramolecular structure of 4aα polymorph is determined.

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Different solvents yield alternative crystal forms through aromatic, halogen bonding and hydrogen bonding competition

CrystEngComm ◽

10.1039/c4ce02109f ◽

2015 ◽

Vol 17 (4) ◽

pp. 877-888 ◽

Cited By ~ 8

Author(s):

Solhe F. Alshahateet ◽

Mohan M. Bhadbhade ◽

Roger Bishop ◽

Marcia L. Scudder

Keyword(s):

Hydrogen Bonding ◽

Acetic Acid ◽

Halogen Bonding ◽

Crystal Forms ◽

X Ray ◽

X Ray Crystallography ◽

Protic Solvents

X-ray crystallography shows that entirely different structures are produced when the dichlorodiquinoline derivative is crystallised from aprotic dimethylformamide or from protic solvents like methanol or acetic acid, demonstrating the importance of solvent choice in yielding alternative crystal forms.

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