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Alumoxanes are typically produced via controlled hydrolysis of short‐chain alkyl aluminium compounds which leads to oligomeric species that are usually difficult to obtain in crystalline form. Simultaneously, various alternative non‐hydrolytic approaches to alumoxanes have also been used. In this work, we report on a new methylalumoxane scaffold derived from the alkylation of a series of dicarboxylic acids: itaconic acid (HO2CCH2C(=CH2)CO2H), succinic acid (HO2CCH2CH2CO2H) and homophthalic acid (HO2CCH2C6H4CO2H). The reactions of AlMe3 with a selected dicarboxylic acid in the molar ratio 4 : 1 conducted at elevated temperature occur with double methylation of each carboxylic group and provide to the formation of a new methylalumoxane aggregate, Me10Al6O4, flanked by methylaluminium diolate units. We also aimed to obtain dialkylaluminium derivatives of dicarboxylic acids by the controlled reaction of the appropriate acid with AlMe3 in the 1 : 2 stoichiometry. While the synthesis of organoaluminium derivatives of flexible aliphatic dicarboxylic acids (itaconic and succinic acids) is challenging due to their insolubility, the related homophtalate compound readily forms a molecular tetranuclear cluster, [([(O2CCH2C6H4CO2)(μ‐AlMe2)2]2. The molecular and crystal structures of the resulting compounds were determined via NMR spectroscopic analysis and single crystal X‐ray diffraction crystallography. [ABSTRACT FROM AUTHOR]

The paper deals with the synthesis of a series of cationic [Pt(ppz)2(N^N)]2+ complexes containing deprotonated 1‐phenyl‐1H‐pyrazole as cyclometallating (C^N) ligands and α‐diimines (N^N) in the form of water‐soluble salts with OTf− (trifluoromethanesulfonate) counter ions. These complexes were obtained from cis‐[Pt(ppz)2Cl2] through chloride ligands substitution with α‐diimines. The complexes were identified by means of NMR spectroscopy and their molecular structures were confirmed by X‐ray crystallography. The photophysical properties of these complexes were studied in detail. These complexes showed strong luminescence in MeOH/EtOH 1 : 1 glasses at 77 K but were almost non‐emitting in MeCN solutions at room temperature. Their emission properties were compared to analogues IrIII complexes. [ABSTRACT FROM AUTHOR]

Simple reaction procedure, boiling of an equimolar mixture of [Re(Cl)(CO)3(dppv)] (dppv—cis-1,2-bis(diphenylphosphino)-ethene), 2-(2-pyridyl)benzimidazole (pbi), and TlClO4 in o-dichlorobenzene solution, leads to two, chromatographically separable, isomers of [Re(CO)2(dppv)(pbi)] complex. The obtained species, the yellow-emissive [OC-6–54] and the orange-emissive [OC-6–53] isomers, have been identified using FT-IR, 1H NMR, and 31P NMR spectroscopy and their structures confirmed by means of X-ray investigations. According to obtained crystallography results, the investigated isomers differ mainly in the arrangement of the 2-(2-pyridyl)benzimidazole anion in their structures. Diverse arrangement of the dppv and pbi ligand around the central cis-[Re(CO)2]+ core results in well-pronounced changes in luminescence properties of the studied luminophores. According to results from performed DFT and TDA-DFT computations, the [OC-6–54] isomer emission occurs from the intra-ligand excitation localized mainly within the pbi ligand. In contrary to that, the [OC-6–53] isomer emission indicates some metal-to-ligand charge-transfer character associated with the charge transfer from the Re(CO)2(dppv)+ fragment to the pbi ligand. Moreover, both isomers exhibit different character of their emission decays, mono-exponential and bi-exponential for the [OC-6–54] and [OC-6–53] ones, respectively. In the view of obtained DFT/TDA-DFT results, this has been explained by the presence of an additional excited dark state, operative only in the case of the [OC-6–53] isomer and associated with the charge transfer from the Re(CO)2(pbi) fragment to the dppv ligand. [ABSTRACT FROM AUTHOR]

10H-1,9-diazaphenothiazine was obtained in the sulphurisation reaction of diphenylamine with elemental sulphur and transformed into new 10-substituted derivatives, containing alkyl and dialkylaminoalkyl groups at the thiazine nitrogen atom. The 1,9-diazaphenothiazine ring system was identified with advanced 1H and 13C NMR techniques (COSY, NOESY, HSQC and HMBC) and confirmed by X-ray diffraction analysis of the methyl derivative. The compounds exhibited significant anticancer activities against the human glioblastoma SNB-19, melanoma C-32 and breast cancer MDA-MB-231 cell lines. The most active 1,9-diazaphenothiazines were the derivatives with the propynyl and N, N-diethylaminoethyl groups being more potent than cisplatin. For those two compounds, the expression of H3, TP53, CDKN1A, BCL-2 and BAX genes was detected by the RT-QPCR method. The proteome profiling study showed the most probable compound action on SNB-19 cells through the intrinsic mitochondrial pathway of apoptosis. The 1,9-diazaphenotiazine system seems to be more potent than known isomeric ones (1,6-diaza-, 1,8-diaza-, 2,7-diaza- and 3,6-diazaphenothiazine). [ABSTRACT FROM AUTHOR]

A series of six [Os(Cl)(CO)(P^P)(pbi)] complexes have been synthesized and characterized using FT-IR, 1H NMR, and 31P NMR spectroscopy. Their molecular structures have been confirmed by means of X-ray diffraction studies. For each of the studied bidentate phosphines (P^P = cis-1,2-bis(diphenylphosphino)ethene – dppv, 1,2-bis(diphenylphosphino)ethane – dppe, 1,2-bis(diphenylphosphino)benzene – dppb) the applied synthesis procedure has afforded preparation of two isomers with pseudo-octahedral coordination of the osmium(II) ion. According to X-ray data, the obtained isomers, green emissive [OC-6-24] and yellow emissive [OC-6-23] species, differ mainly in the arrangement of the 2-(2-pyridyl)benzimidazolate (pbi) anion in their structures. In the [OC-6-24] isomers the benzoimidazole fragment of the pbi ligand is located trans to the coordinated CO molecule, whereas the cis conformation is characteristic of the [OC-6-23] isomers. Each of trans-[Os(Cl)(CO)(P^P)(pbi)] shows intense green emission attributable to the excited triplet state of the pbi ligand, whereas the yellow emission from the excited cis-[Os(Cl)(CO)(P^P)(pbi)] indicates slight metal-to-ligand charge transfer character (from the Os(Cl)(CO)(P^P)+ fragment to the pbi ligand). The investigated complexes are generally well emissive with emission quantum yields up to 0.49 and emission lifetimes in the range of 10–150 μs. Only the yellow emissive cis-[Os(Cl)(CO)(dppv)(pbi)] complex exhibits remarkably different photophysical behaviour despite the fact that all three cis-[Os(Cl)(CO)(P^P)(pbi)] isomers emit in the same spectral region. In the view of DFT/TD-DFT results this has been explained by the presence of an additional excited dark state possessing distinct charge transfer character (from the Os(Cl)(CO)(pbi) fragment to the dppv ligand). [ABSTRACT FROM AUTHOR]

The additive and antagonistic effects of the substrates and vapors on morphology of glycyl-glycine film were observed. The direction of joint effect significantly depends on the ability of the organic compound to form hydrogen bond. The vapors of strong H-donor or H-acceptor are able to overcome the interaction of the dipeptide molecules with substrate and change the film morphology. The Hansen solubility parameters can be used to predict the ability of vapors to initiate the self-assembly of dipeptide in solid state. The possible mechanism of glycyl-glycine self-assembly in solid state was proposed. [ABSTRACT FROM AUTHOR]

Intramolecular electron transfer over the sp3-C-link in dimethyl-aniline-spiro-phthalide leads to extreme solvatofluorochromism (11 600 cm−1) and a fluorescence maximum shift from 357 (hexane) to 595 nm (acetonitrile). The spiro link enhances π–σ* negative hyperconjugation leading to C–O bond elongation and electron transfer over a longer distance than in a non-spirocyclic analogue. [ABSTRACT FROM AUTHOR]

The paper presents results concerning construction of inclusion complexes of para-sulphonato-calix[8]arene with 1,10-phenanthroline. Structures of crystalline host–guest complexes were determined by means of X-ray diffraction. Intermolecular interactions were analyzed and the organization of ions and molecules in the crystal lattice was described. [ABSTRACT FROM AUTHOR]

3,6-Diazaphenothiazines were obtained in cyclization of 3-amino-3′-nitro-2,4′-dipyridinyl sulfide and the reaction of sodium 3-amino-2-pyridinethiolate with 4-chloro-3-nitropyridine followed by alkylation and heteroarylation. The thiazine ring formation ran via the Smiles rearrangement. The structure elucidation was based on 2D NMR and X-ray analysis ofN-methylated product. 3,6-Diazaphenothiazines were investigated for antitumor activity using glioblastoma SNB-19, melanoma C-32 and breast cancer MCF-7 cells. 10H-3,6-diazaphenothiazine was 10 times more active (IC50 < 0.72 μg/mL) than cisplatin. Two diazaphenothiazines with the 2-pyrimidinyl and dimethylaminopropyl substituents were selectively active against MCF-7 and C-32 cells. The expressions ofH3(proliferation marker),TP53, CDKN1A(cell cycle regulators), BAXandBCL-2(proapoptopic and antiapoptopic genes) were detected by RT-QPCR method. The expression analysis suggests the cell cycle arrest and the mitochondrial apoptosis pathway activation in MCF-7 and SNB-19 cells. [ABSTRACT FROM PUBLISHER]

Two series of cationic heteroleptic osmium(ii) complexes with a coordinated CO molecule, a chloride Cl− or hydride H− anion, two monodentate triphenylphosphine (tpp) ligands and one bidentate α-dimine (N∧N) ligand were prepared from an OsCl2(CO)2(tpp)2 precursor. The investigated complexes, available in the form of PF6− salts, have been identified by means of FT-IR, 1H and 31P NMR spectroscopy and X-ray diffraction studies. Their photophysical properties have been investigated in dichloromethane solutions at room temperature and 1 : 1 ethanol–methanol matrices at 77 K. The investigated complexes exhibit metal to ligand charge-transfer (MLCT) phosphorescence with the emission characteristics distinctly affected by the nature of coordinated α-diimine N∧N and Cl− or H− ligands. Franck–Condon emission spectral band shape analyses and DFT/TD-DFT calculations have been applied to obtain more detailed insight into the nature of emissive 3*[Os(H)(CO)(N∧N)(tpp)2]+ and 3*[Os(Cl)(CO)(N∧N)(tpp)2]+ species. [ABSTRACT FROM AUTHOR]