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Studies of the supramolecular chemistry of iso‐tellurazole N‐oxides have been confined to non‐polar media until now. To overcome that limitation, an iso‐tellurazole N‐oxide was derivatized with a primary alcohol group; the compound is soluble in polar solvents and stable in acidic to neutral aqueous media. Nickel (II) and iron (II) form macrocyclic complexes with six molecules of that iso‐tellurazole N‐oxide in a hitherto not‐observed macrocyclic arrangement defined by CTe⋅⋅⋅O chalcogen bonds and κ6‐O bound to the metal ion. This behaviour is in sharp contrast with the κn‐Te (n=1,2,4) complexes formed by soft metal ions. [ABSTRACT FROM AUTHOR]

Iso-tellurazole N-oxides are promising supramolecular building blocks. While in neutral solutions, they form tetra-and hexameric macrocyclic aggregates linked by Te ... O secondary bonding (t hole interactions or chalcogen bonds), protonation of the oxygen atom in acidic media disrupts such supramolecular association. The process is reversible and, consequently, can be used to switch on and off the self-assembly process. Hammett acidity measurements gave p[K.sub.a] values of-3.2 for the protonated molecules. Adducts with HCl and HBr were isolated and structurally characterized. Protonation in solution led to the crystallization of a new polymorph of 3-methyl-5-phenyl-1,2- tellurazole N-oxide, which features a unique polymeric arrangement. Key words: sigma-hole interactions, secondary bonding, chalcogens, supramolecular chemistry, main-group chemistry. Les isotellurazoles N-oxydes sont des synthons supramoleculaires prometteurs. Bien qu'en solution neutre, ils forment des agregats macrocycliques tetrameriques et hexameriques retenus par des liaisons secondaires Te ... O (interactions de trous t ou liaisons chalcogene), en milieu acide, la protonation des atomes d'oxygene perturbe une association supramoleculaire de ce type. Ce processus d'association est reversible et peut donc etre utilise pour provoquer ou inhiber le processus d'autoassamblage. Nous avons calcule, pour les molecules protonees, une valeur de p[K.sub.a] de -3,2 derivee des mesures de l'acidite en utilisant l'equation de Hammett. En outre, nous avons isole des adduits de HCl et de HBr et en avons caracterise les structures. La protonation en solution a entraine la cristallisation d'un nouveau polymorphe du 3-methyl-5-phenyl-1,2-tellurazole Noxyde presentant une structure polymerique unique. [Traduit par la Redaction] Mots-cles : interactions de trous sigma, liaison secondaire, chalcogenes, chimie supramoleculaire, chimie du groupement principal., Introduction The remarkable success of halogen bonding (1-4) in areas as diverse as crystal engineering, (2,5-14) supramolecular catalysis, (15) anion recognition, (16) optical materials, (17) and biomimetic chemistry (18-20) has [...]

Systematic theologians have constructed a Christology that is highly based on NT texts, which, interestingly, supports the anachronistic reading sustained by Psalms scholarship over the last two centuries. In contrast, this paper argues for a forward reading that supports the Psalms as intrinsically messianic. Methodologically, I study the Davidic psalms in five collections, giving emphasis to the superscriptions, structural form, and content. My observations show that the Davidic psalms first trace the establishment of the Davidic kingship, followed by his downfall. Then, remarkably, the Davidic characterization shifts to a royal figure, who is blameless, victorious, and juridically condemned. The final Davidic collection reveals a community of people supplicating patiently before the arrival of a blissful and just society. The paper shows that the NT's understanding of Jesus fulfilling the messianic hopes in the Psalter is a formidable and reasonable interpretation and need not be anachronistic. [ABSTRACT FROM AUTHOR]

The reactions of iso-tellurazole N-oxides with monocations of the coinage metals yielded a family of coordination complexes with a remarkable variety of compositions and structures. All new species were identified by single-crystal X-ray diffraction. In all cases, the macrocyclic aggregation of the organo-chalcogen heterocycles through Te⋯O chalcogen bonding interactions is preserved and the metal ions are coordinated by tellurium. Copper and gold formed complexes with the tetramers. The lighter element acquired a κ4Te,κ1O pentacoordinated square pyramidal structure with a triflate anion in the apical position. The preference of the heavier metal for a linear κ1Te,κ1Cl coordination geometry permitted the formation of a binuclear complex. Silver demonstrated a unique preference for coordinating to the hexamer; two distinct examples showed a structure with a pair of endocyclic κ2Te,κ2O metal ions bridged by two triflate anions; the other two chalcogen atoms are located at trans-annular positions and each coordinates a κ1Te,κ1O,κ1C silver ion, also bonded to an aromatic carbon and another triflate anion. [ABSTRACT FROM AUTHOR]

The DJIA components represent large, well-established companies that constitute nearly 30 percent of the market value of all stocks of the NYSE. They are regarded as fundamentally sound. The DJIA was use as market index since the requisite data were readily available. IT was observed that communality associated with the DJIA was nearly 100 percent. This is not a typical event. The abstraction of the variability of the DJIA into common factors allows us in making use of the structure by choosing those subsets of the DJIA that also have high communalities. Hence the resulting subset may be regarded as a portfolio whose behavior is highly correlated with the index itself.

Studies of the supramolecular chemistry of iso-tellurazole N-oxides have been confined to non-polar media until now. To overcome that limitation, an iso-tellurazole N-oxide was derivatized with a primary alcohol group; the compound is soluble in polar solvents and stable in acidic to neutral aqueous media. Nickel (II) and iron (II) form macrocyclic complexes with six molecules of that iso-tellurazole N-oxide in a hitherto not-observed macrocyclic arrangement defined by CTe⋅⋅⋅O chalcogen bonds and κ 6 -O bound to the metal ion. This behaviour is in sharp contrast with the κ n -Te (n=1,2,4) complexes formed by soft metal ions., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Chlorination of 3-methyl-5-phenyl-1,2-tellurazole-2-oxide yielded the λ 4 Te dichloro derivative. Its crystal structure demonstrates that the heterocycle retains its ability to autoassociate by chalcogen bonding (ChB) forming macrocyclic tetramers. The corresponding Te⋅⋅⋅O ChB distances are 2.062 Å, the shortest observed to date in aggregates of this type. DFT-D3 calculations indicate that while the halogenated molecule is stronger as a ChB donor it also is a weaker ChB acceptor; the overall effect is that the ChBs in the chlorinated homotetramer are not significantly stronger. However, partial halogenation or scrambling selectively yield the 2 : 2 heterotetramer with alternating λ 4 Te and λ 2 Te centers, which calculations identified as the thermodynamically preferred arrangement., (© 2021 Wiley-VCH GmbH.)