Reactions of (di-)bromo-substituted CF3-allyl alcohols with/without arenes with TfOH lead to CF3-alkenes or CF3-indenes.

A 1, 3,5,7,3,6, chloride platinumIJII) complex (1) was obtained via the metal-mediated double coupling of 2,3-diphenylmaleimidine with both nitrile ligands in trans-Compound 1 was then co-crystallized with diiodomethane forming solvate 1·½CH 2 I 2 . The XRD experiment reveals that this solvate displays the halogen bonds H 2 C(I)-I⋯Cl-Pt and hydrogen bonds I 2 C(H)-H⋯Cl-Pt, which join two complex and one CH 2 I 2 molecules in a heterotrimeric supramolecular cluster. Inspection of the CCDC database reveals only one example of the halogen bond H 2 C(I)-I⋯I-Pt between the CH 2 I 2 molecule and metal-coordinated halide in the structure of VEMWOA. In VEMWOA, CH 2 I 2 serves solely as a halogen bond donor with no hydrogen bond contribution. Results of the Hirshfeld surface analysis and DFT calculations (M06/DZP-DKH level of theory) followed by topological analysis of the electron density distribution within the formalism of Bader's theory (QTAIM method) for both 1·½CH 2 I 2 and VEMWOA confirmed the formation of these weak interactions. The evaluated energies of halogen bonds involving CH 2 I 2 are in the 2.2-2.8 kcal mol −1 range.

receptors CB 1 and CB 2 types. The most potent compound showed sub-micromolar affinity for both receptor subtypes with a 6-fold selectivity toward the CB 2 receptor with no appreciable cytotoxicity toward SHSY5Y cells.

The reaction of cis-[PdCl(CNXyl)] (Xyl = 2,6-MeCH) with the aminoazoles [1 H-imidazol-2-amine (1), 4 H-1,2,4-triazol-3-amine (2), 1 H-tetrazol-5-amine (3), 1 H-benzimidazol-2-amine (4), 1-alkyl-1 H-benzimidazol-2-amines, where alkyl = Me (5), Et (6)] in a 2:1 ratio in the presence of a base in CHCl at RT proceeds regioselectively and leads to the binuclear diaminocarbene complexes [(ClPdCNXyl){μ-C(N-azolyl)N(Xyl)C═NXyl}] (7-12; 73-91%). Compounds 7-12 were characterized by C, H, N elemental analyses, high-resolution ESI-MS, Fourier transform infrared spectroscopy, 1D (H, C) and 2D (H,H-COSY, H,H-NOESY, H,C-HSQC, H,C-HMBC) NMR spectroscopies, and X-ray diffraction (XRDn). Inspection of the XRDn data and results of the Hirshfeld surface analysis suggest the presence in all six structures of intramolecular π-hole···π interactions between the electrophilic C atom of the isocyanide moiety and the neighboring arene ring. These interactions also result in distortion of the Pd-C≡N-Xyl fragment from the linearity. Results of density functional theory calculations [M06/MWB28 (Pd) and 6-31G* (other atoms) level of theory] for model structures of 7-9 followed by the topological analysis of the electron density distribution within the framework of Bader's theory (QTAIM method) reveal the presence of these weak interactions also in a CHCl solution, and their calculated strength is 1.9-2.2 kcal/mol. The natural bond orbital analysis of 7-9 revealed that π(C-C)Xyl → π*(C-N)isocyanide charge transfer (CT) takes place along with the intramolecular π-hole···π interactions. The observed π(C-C) → π*(C-N) CT is due to ligation of the isocyanide to the metal center, whereas in the cases of the uncomplexed p-CNCHNC and CNXyl species, the effects of CT are negligible. Available CCDC data were processed from the perspective of isocyanide-involving π-hole···π interactions, disclosed the role of metal coordination in the π-hole donor ability of isocyanides, and verified the π-hole···π interaction effect on the stabilization of the in-conformation in metal-bound acyclic diaminocarbenes.

Take-down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Structures and photophysical properties of 3,4-diaryl-1H-pyrrol-2,5diimines and 2,3-diarylmaleimides

The crystal structures of natural (Mt. Koashva, Khibiny alkaline massif, Kola Peninsula, Russian Arctic) and synthetic (obtained from an aqueous solution of sodium phosphate and sodium fluoride (1:1) by evaporation at room temperature (RT)) natrophosphate, Na7(PO4)2F·19H2O, have been investigated using single-crystal X-ray diffraction analysis. Natrophosphate and its synthetic analogue are cubic, Fd-3c, a = 27.6942(3) Å (natrophosphate at RT), a = 27.6241(4) Å (natrophosphate at 100 K), a = 28.1150(12) Å (synthetic analogue at RT), a = 27.9777(7) Å (synthetic analogue at 100 K). The crystal structure is based upon the super-octahedral [Na6(H2O)18F]5+ polycationic complexes consisting of six edge-linked Na6(OH2)5F octahedra sharing one common fluorine vertex. The A site is statistically occupied by Na and H2O with the prevalence of H2O with the refined occupancy factors O:Na equal to 0.53:0.47 for natrophosphate and 0.75:0.25 for its synthetic analogue. The coordination of the A site in synthetic natrophosphate is enlarged compared to the natural sample, which agrees well with its higher occupancy by H2O molecules. The general formula of natrophosphates can be written as Na6+xHxF(PO4)2·(19 + x)H2O, where x = 0–1. The chemical variability of natrophosphate allows to explain the discrepancies in its solubility reported by different authors. The information-based parameters of structural complexity are equal to 3.713 bit/atom and 2109.177 bit/cell that allows to classify natrophosphate as a structurally very complex mineral.

The complexities of chemical composition and crystal structure are fundamental characteristics of minerals that have high relevance to the understanding of their stability, occurrence and evolution. This review summarises recent developments in the field of mineral complexity and outlines possible directions for its future elaboration. The database of structural and chemical complexity parameters of minerals is updated by H-correction of structures with unknown H positions and the inclusion of new data. The revised average complexity values (arithmetic means) for all minerals are 3.54(2) bits/atom and 345(10) bits/cell (based upon 4443 structure reports). The distributions of atomic information amounts, chemIG and strIG, versus the number of mineral species fit the normal modes, whereas the distributions of total complexities, chemIG,total and strIG,total, along with numbers of atoms per formula and per unit cell are log normal. The three most complex mineral species known today are ewingite, morrisonite and ilmajokite, all either discovered or structurally characterised within the last five years. The most important complexity-generating mechanisms in minerals are: (1) the presence of isolated large clusters; (2) the presence of large clusters linked together to form three-dimensional frameworks; (3) formation of complex three-dimensional modular frameworks; (4) formation of complex modular layers; (5) high hydration state in salts with complex heteropolyhedral units; and (6) formation of ordered superstructures of relatively simple structure types. The relations between symmetry and complexity are considered. The analysis of temporal dynamics of mineralogical discoveries since 1875 with the step of 25 years show the increasing chemical and structural complexities of human knowledge of the mineral kingdom in the history of mineralogy. In the Earth's history, both diversity and complexity of minerals experience dramatic increases associated with the formation of Earth's continental crust, initiation of plate tectonics and the Great Oxidation event.

The reactions of 3‐bromo‐ and 3,4‐dibromo‐CF3‐enones with superacids were studied. Protonation of these CF3‐enones with FSO3H resulted in the formation of cationic species that subsequently cyclized at –60 °C to give the corresponding mono‐ and dibromoindenols in up to 98 % yield. Protonation of the indenol products at room temperature with triflic acid (CF3SO3H) provided highly electrophilic trifluoromethylated indenyl cations. Subsequent reaction with various arenes gave access to 1‐CF3‐substituted indenes in up to 84 % yields. DFT calculations were carried out to obtain data about the electronic structure and electrophilicity of the cationic intermediates. The mechanisms of these multistep transformations of highly electrophilic cationic intermediates are discussed.