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Group 16 chalcogens potentially provide Lewis‐acidic σ‐holes, which are able to form attractive supramolecular interactions with electron rich partners through chalcogen bonds. Here, a multifaceted experimental and computational study of a large series of novel chalcogen‐bonded cocrystals, prepared using the principles of crystal engineering, is presented. Single‐crystal X‐ray diffraction studies reveal that dicyanoselenadiazole and dicyanotelluradiazole derivatives work as promising supramolecular synthons with the ability to form double chalcogen bonds with a wide range of electron donors including halides and oxygen‐ and nitrogen‐containing heterocycles. Extensive 77Se and 125Te solid‐state nuclear magnetic resonance spectroscopic investigations of cocrystals establish correlations between the NMR parameters of selenium and tellurium and the local chalcogen bonding geometry. The relationships between the electronic environment of the chalcogen bond and the 77Se and 125Te chemical shift tensors were elucidated through a natural localized molecular orbital density functional theory analysis. This systematic study of chalcogen‐bond‐based crystal engineering lays the foundations for the preparation of the various multicomponent systems and establishes solid‐state NMR protocols to detect these interactions in powdered materials. [ABSTRACT FROM AUTHOR]

Macrocycle formation that relies upon trans metal coordination of appropriately placed pyridine ligands within an arylene ethynylene construct provides rapid and reliable access to molecular rotators encapsulated within macrocyclic stators. Showing no significant close contacts to the central rotators, X‐ray crystallography of AgI‐coordinated macrocycles provides plausibility for unobstructed rotation or wobbling of rotators within the central cavity. Solid‐state 13C NMR of PdII‐coordinated macrocycles supports the notion of unobstructed movement of simple arenes in the crystal lattice. Solution 1H NMR studies indicate complete and immediate macrocycle formation upon the introduction of PdII to the pyridyl‐based ligand at room temperature. Moreover, the formed macrocycle is stable in solution; a lack of significant changes in the 1H NMR spectrum upon cooling to −50 °C is consistent with the absence of dynamic behavior. The synthetic route to these macrocycles is expedient and modular, providing access to rather complex constructs in four simple steps involving Sonogashira coupling and deprotection reactions. [ABSTRACT FROM AUTHOR]

Frontispiece: Double Chalcogen Bonds: Crystal Engineering Stratagems via Diffraction and Multinuclear Solid-State Magnetic Resonance Spectroscopy Keywords: chalcogen bonds; crystal engineering; dicyanoselenadiazole; dicyanotelluradiazole; molecular orbital analysis; solid-state NMR Chalcogen bonds, crystal engineering, dicyanoselenadiazole, dicyanotelluradiazole, molecular orbital analysis, solid-state NMR. [Extracted from the article]

Keywords: arylene ethynylenes; crystal engineering; macrocycles; metal complexes; molecular rotors EN arylene ethynylenes crystal engineering macrocycles metal complexes molecular rotors 1 1 1 09/11/23 20230906 NES 230906 B We've got you surrounded b ! Arylene ethynylenes, crystal engineering, macrocycles, metal complexes, molecular rotors Cover Feature: Rapid Access to Encapsulated Molecular Rotors via Coordination-Driven Macrocycle Formation (Chem. Eur. J. 50/2023). [Extracted from the article]

Abstract: Halogen bonding is an increasingly important tool in crystal engineering, and measuring its influence on the local chemical and electronic environment is necessary to fully understand this interaction. Here, we present a systematic crystallographic and solid‐state NMR study of self‐complementary halogen‐bonded frameworks built from the halide salts (HCl, HBr, HI, HI3) of 2‐iodoethynylpyridine and 3‐iodoethynylpyridine. A series of single crystal X‐ray structures reveals the formation of discrete charged dimers in the solid state, directed by simultaneous X−⋅⋅⋅H−N+ hydrogen bonds and C−I⋅⋅⋅X− halogen bonds (X=Cl, Br, I). Each compound was studied using multinuclear solid‐state magnetic resonance spectroscopy, observing 1H to investigate the hydrogen bonds and 13C, 35Cl, and 79/81Br to investigate the halogen bonds. A natural localized molecular orbital analysis was employed to help interpret the experimental results. 1H SSNMR spectroscopy reveals a decrease in the chemical shift of the proton participating in the hydrogen bond as the halogen increases in size, whereas the 13C SSNMR reveals an increased 13C chemical shift of the C−I carbon for C−I⋅⋅⋅X− relative to C−I⋅⋅⋅N halogen bonds. Additionally, 35Cl and 79/81Br SSNMR, along with computational results, have allowed us to compare the C−I⋅⋅⋅X− halogen bond involving each halide in terms of NMR observables. Due to the isostructural nature of these compounds, they are ideal cases for experimentally assessing the impact of different halogen bond acceptors on the solid‐state NMR response. [ABSTRACT FROM AUTHOR]