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The stability of hybrid organic–inorganic halide perovskite semiconductors remains a significant obstacle to their application in photovoltaics. To this end, the use of low‐dimensional (LD) perovskites, which incorporate hydrophobic organic moieties, provides an effective strategy to improve their stability, yet often at the expense of their performance. To address this limitation, supramolecular engineering of noncovalent interactions between organic and inorganic components has shown potential by relying on hydrogen bonding and conventional van der Waals interactions. Here, the capacity to access novel LD perovskite structures that uniquely assemble through unorthodox S‐mediated interactions is explored by incorporating benzothiadiazole‐based moieties. The formation of S‐mediated LD structures is demonstrated, including one‐dimensional (1D) and layered two‐dimensional (2D) perovskite phases assembled via chalcogen bonding and S–π interactions. This involved a combination of techniques, such as single crystal and thin film X‐ray diffraction, as well as solid‐state NMR spectroscopy, complemented by molecular dynamics simulations, density functional theory calculations, and optoelectronic characterization, revealing superior conductivities of S‐mediated LD perovskites. The resulting materials are applied in n‐i‐p and p‐i‐n perovskite solar cells, demonstrating enhancements in performance and operational stability that reveal a versatile supramolecular strategy in photovoltaics. [ABSTRACT FROM AUTHOR]

Phosphate-based materials are of great interest in the design of solid electrolytes for sodium ion batteries. The synthesis, crystal structure and ionic conductivity of tetrasodium hypodiphosphate are reported. The nanocrystalline anhydrous material, Na4(P2O6), was obtained by dehydration and its crystal structure was determined with 3D electron and X-ray powder diffraction. The effect of chemical modification on the structure and conductivity of the title compound in comparison with its analogues is revealed. [ABSTRACT FROM AUTHOR]

Reactions between 1,2-di(tetrazol-2-yl)ethane (ebtz), 1,6-di(tetrazol-2-yl)hexane (hbtz) or 1,1′-di(tetrazol-1-yl)methane (1ditz) and Fe(BF4)2 in the presence of adiponitrile (ADN), glutaronitrile (GLN) or suberonitrile (SUN) resulted in the formation of coordination polymers [Fe(μ-ebtz)2(μ-ADN)](BF4)2 (1), [Fe(μ-hbtz)2(μ-ADN)](BF4)2 (2), [Fe(μ-1ditz)2(GLN)2](BF4)2·GLN (3) and [Fe(μ-1ditz)2(μ-SUN)](BF4)2·SUN (4). It was established that the application of dinitriles allows an increase in the dimensionality of the ebtz and hbtz based systems while maintaining the structure of the polymeric units characteristic of previously studied mononitrile based analogues. In 3 and 4, regardless of the type of dinitrile coligand, the motif of 2D polymeric layers constituted by 1ditz molecules remains preserved. However, the dimensionality of 1ditz based networks is governed by the coordination modes of dinitriles. 3, based on a shorter molecule of glutaronitrile, crystallizes as a two-dimensional (2D) coordination polymer. In this compound, dinitriles coordinate monodentately or play the role of guest molecules. The substitution of glutaronitrile with suberonitrile enables the bridging of neighboring polymeric layers, resulting in a 3D network. The intentional selection of bis(tetrazoles) and dinitriles as building blocks has led, as expected, to obtaining systems with the structure of the first coordination sphere consisting of four tetrazole rings and two axially coordinated nitrile molecules. It created the conditions required for the occurrence of thermally induced spin crossover. Magnetic measurements and single crystal X-ray diffraction studies were used for the characterization of the spin crossover properties of 1–4. [ABSTRACT FROM AUTHOR]

A diradical/biradical character of organic derivatives is one of the key aspects of contemporary research focusing on the fundamental studies followed by potential applicability relying on the unique optical, electronic, or magnetic properties assigned to unpaired electrons. A precise involvement of two p‐phenylenes into a cyclophane‐like conjugated, diatropic system creates a flexible molecule with the two different characters of both subunits (benzene and quinone) imprinting into the structure a Kekulé delocalized system. A dynamic of both carbocyclic subunits, and their mutual interaction generates a singlet open‐shell state (J=−1.25 kcal/mol) as documented spectroscopically (NMR and EPR). The extended theoretical analysis has proved a correlation between dihedral angle and the diradicaloid character that shifts from a closed‐shell singlet to an open‐shell state, eventually showing the y0=0.86 for 78 degrees and ΔEST=−0.34 kcal/mol. [ABSTRACT FROM AUTHOR]

Platinum complexes [PtCl2(L)] L = L1, L2 with symmetrical HP (OCH2CMe2NH)2 (L1) and unsymmetrical HP(OCMe2CMe2O)(OCH2CMe2NH) (L2) hydrospirophosphorane (HSP) ligands were demonstrated to play a dual role of catalysts and cytotoxic compounds as well. The structure of new complex [PtCl2(L2)] was confirmed by physicochemical and spectroscopic methods, as well as single X‐ray diffraction studies for [PtCl2{P (OCMe2CMe2O)(OCH2CMe2NH2)}]. HSP ligand coordinated to the platinum center in bidentate κ2‐P,NH2 chelating mode of fashion. Both complexes were found to exhibit catalytic activity for Heck cross‐coupling reactions of iodobenzene with substituted styrenes, with good conversion and yield of stilbenes. Moreover, complexes have been applied as excellent catalysts for highly regioselective hydrosilylation of aromatic and aliphatic terminal olefins, and acetylenes terminal and internal as well. On the other hand, the preliminary biological studies revealed that in the presence of foretinib, drug candidate in clinical trials for the treatment of cancer, platinum complexes revealed increased synergistic effect and efficiently decreased the number of viable cells of triple negative breast cancer MDA‐MB‐231 cell line. [ABSTRACT FROM AUTHOR]

Reaction of 1,2‐di(tetrazol‐2‐yl)ethane (ebtz) with Fe(BF4)2⋅6 H2O in different nitriles yields one‐dimensional coordination polymers [Fe(ebtz)2(RCN)2](BF4)2⋅nRCN (n=2 for R=CH3 (1) and n=0 for R=C2H5 (2) C3H7 (3), C3H5 (4), CH2Cl (5)) exhibiting spin crossover (SCO). SCO in 1 and 3–5 is complete and occurs above 160 K. In 2, it is shifted to lower temperatures and is accompanied by wide hysteresis (T1/2↓=78 K, T1/2↑=123 K) and proceeds extremely slowly. Isothermal (80 K) time‐resolved single‐crystal X‐ray diffraction studies revealed a complex nature for the HS→LS transition in 2. An initial, slow stage is associated with shrinkage of polymeric chains and with reduction of volume at 77 % (in relation to the difference between cell volumes VHS−VLS) whereas only 16 % of iron(II) ions change spin state. In the second stage, an abrupt SCO occurs, associated with breathing of the crystal lattice along the direction of the Fe–nitrile bonds, while the nitriles reorient. HS→LS switching triggered by light (808 nm) reveals the coupling of spin state and nitrile orientation. The importance of this coupling was confirmed by studies of [Fe(ebtz)2(C2H5CN/C3H7CN)2](BF4)2 mixed crystals (2 a, 2 b), showing a shift of T1/2 to higher values and narrowing of the hysteresis loop concomitant with an increase of the fraction of butyronitrile. This increase reduces the capability of nitrile molecules to reorient. Density functional theory (DFT) studies of models of 1–5 suggest a particular possibility of 2 to adopt a low (140–145°) value of its Fe‐N‐C(propionitrile) angle. [ABSTRACT FROM AUTHOR]

3-(Thien-2-yl)- and 3-(thien-3-yl)allylamines, readily accessible from the corresponding thienyl aldehydes, can interact with a broad range of anhydrides and α,β-unsaturated acids chlorides (maleic, сitraconic-, and phenyl maleic anhydrides, сrotonyl and сinnamyl chlorides, etc.) leading to the formation of a thieno[2,3- f ]isoindole core. Usually, the reaction sequence involves three successive steps: acylation of the nitrogen atom of the initial allylamine, the intramolecular Diels–Alder vinylarenе (IMDAV) reaction, and the final aromatization of the dihydrothiophene ring in the Diels–Alder adducts. The scope and limitations of the proposed method were thoroughly investigated. It was revealed with the aid of X-ray analysis that the key step, the IMDAV reaction, proceeds through an exo -transition state, giving rise to the exclusive formation of a single diastereomer of the target heterocycle. In the case of maleic anhydrides, the method allows to obtain functionally substituted thieno[2,3- f ]isoindole carboxylic acids, which are potentially useful substrates for further transformations and subsequent bioscreening. [ABSTRACT FROM AUTHOR]