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Ammonium oxathioamidate (1) was synthesised by the reaction between O-ethyl-thioxamate (oxalic acid-1-amide-2-O-ethyl ester) and ammonium hydrogen carbonate in water solution. Compound 1 was fully characterised by both microanalytical (elemental analysis, melting point determination) and spectroscopic means (FT-IR and NMR spectroscopy). Crystals suitable for single-crystal X-ray diffraction were isolated by slow evaporation of an ethanol solution of the compound. The analysis of the crystal packing reveals the prominent role exerted by intermolecular hydrogen bonding (HB) and chalcogen bonding (ChB) interactions. [ABSTRACT FROM AUTHOR]

Although known for 120 years, the title compound has not been adequately characterised before. In this paper, it is fully characterised by 1H and 13C NMR and IR spectroscopy and its X-ray structure has been determined for the first time. [ABSTRACT FROM AUTHOR]

We have designed a highly twisted small thermally activated delayed fluorescence (TADF) emitter PXZ-[alpha]-DK based on an [alpha]-diketone ([alpha]-DK) as a strong acceptor and phenoxazine (PXZ) as a strong donor to obtain red-shifted emission in comparison with the equivalent [alpha]-diketone linked to 9,9-dimethyl-9,10-dihydroacridine (DMAC). The PXZ-[alpha]-DK shows emission at 586 nm and DMAC-[alpha]-DK shows emission at 548 nm in 1,3-bis(N-carbazolyl)benzene (mCP) host at 1.5 wt% doping of the emitter, with short-delayed lifetimes of 6.9 ls for PXZ-[alpha]-DK and 7.6 ls for DMAC-[alpha]-DK. Organic light-emitting diodes (OLEDs) fabricated using these emitters show green electroluminescence at 555 nm for DMAC-[alpha]-DK, with a maximum external quantum efficiency, [EQE.sub.max], of 6.3%, and orange electroluminescence at 585 nm for PXZ-[alpha]-DK, with an [EQE.sub.max] of 0.8%. We corroborate the optoelectronic properties of these emitters with DFT calculations. Key words: TADF, OLEDs, [alpha]-diketone, red-shifted emission. Nous avons concu un emetteur de fluorescence retardee activee thermiquement (TADF pour Thermally Activated Delayed Fluorescence) a haut degre de torsion, PXZ-[alpha]-DK, a partir d'une [alpha]-dicetone (aDK) comme groupe accepteur fort et de la phenoxazine (PXZ) comme groupe donneur fort pour obtenir une emission deplacee vers le rouge par rapport a l'analogue constitue de l' adicetone liee a la 9,9dimethyl-9,10dihydroacridine (DMAC). La PXZaDK presente une emission a 586 nm et la DMACaDK, une emission a 548 nm dans une matrice hote de 1,3bis(N-carbazolyl)benzene (mCP) a un taux de dopage de l'emetteur de 1,5 % p/p, le temps de vie retarde de courte duree etant de 6,9 ls pour la PXZaDK et de 7,6 ls pour la DMACaDK. Les diodes electroluminescentes organiques (DELO) fabriquees a l'aide de ces emetteurs presentent une electroluminescence verte a 555 nm avec une efficacite quantique externe maximale ([EQE.sub.max]) de 6,3 % dans le cas de la DMACaDK, et une electroluminescence orange a 585 nm avec une [EQE.sub.max] de 0,8 % dans le cas la PXZaDK. Nous corroborons les proprietes optoelectroniques de ces emetteurs par des calculs DFT. [Traduit par la Redaction] Mots-cles : TADF, DELO, [alpha]-dicetone, emission deplacee vers le rouge., Introduction Since the seminal report of Adachi and co-workers in 2012, (1) organic light-emitting diodes (OLEDs) employing organic thermally activated delayed fluorescence (TADF) emitters have received significant attention because of [...]

The title compound and its hydroxymethyl precursor have been fully characterised for the first time. The IR spectra, fully assigned 1H and 13C NMR spectra, and X-ray structures are presented for both compounds. Both compounds form hydrogen-bonded dimers in the crystal structures. [ABSTRACT FROM AUTHOR]

X-ray crystallography has been used to characterize the title compound for the first time; 1H NMR, 13C NMR and IR spectroscopic data have also been updated from earlier reports. We also report the melting point of the title compound. [ABSTRACT FROM AUTHOR]

The bidentate ligand, 1,4-bis(diphenlyphosphoryl)butane (dppbO2), was used to prepare a 1D polymeric Pr(III) complex which was characterised by single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

Malamides (diamide derivatives of malic acid) are prevalent in nature and of significant biological interest, yet only limited synthetic methods to access functionalised enantiopure derivatives have been established to date. Herein, an effective synthetic method to generate this molecular class is developed through in situ formation of spirocyclic β-lactone-oxindoles (employing a known enantioselective isothiourea-catalysed formal [2+2] cycloaddition of C(1)-ammonium enolates and isatin derivatives) followed by a subsequent dual ring-opening protocol (of the β-lactone and oxindole) with amine nucleophiles. The application of this protocol is demonstrated across twelve examples to give densely functionalised malamide derivatives with high enantio- and diastereo-selectivity (up to >95:5 dr and >99:1 er). [ABSTRACT FROM AUTHOR]

Two salts of the chlorhexidine di-cation (H2CHx2+) - (H2CHx)(SO4)·3H2O and (H2CHx)(CO3)·4H2O - have been synthesised and characterised crystallographically.

A simplified synthesis of the title compound is reported and its 1H and 13C NMR data are fully assigned including determination of H–H and C–H coupling constants. Its X-ray structure has been determined for the first time. NMR data are also presented for the oxygen analogue. [ABSTRACT FROM AUTHOR]

A highly reactive dicuprate/CuCl aggregate, Nap(Cu4Cl2)(TMEDA)2 (2, Nap = naphthalene-1,8-diyl, TMEDA = tetramethylethylenediamine), was synthesized by the reaction of 1,8-dilithionaphthalene(TMEDA)2 with four equivalents of CuCl. The X-ray crystal structure of this complex shows that the four copper atoms form a bent parallelogram-shaped core, with terminally bonded chlorine atoms. The naphthalene ring is bonded through carbons in the 1 and 8 positions (peri-positions), each bridging two copper atoms. [ABSTRACT FROM AUTHOR]

Two mixed peri-substituted phosphine-chlorostibines, Acenap(PiPr2)(SbPhCl) and Acenap(PiPr2)(SbCl2) (Acenap = acenaphthene-5,6-diyl) reacted cleanly with Grignard reagents or nBuLi to give the corresponding tertiary phosphine-stibines Acenap(PiPr2)(SbRR') (R, R' = Me, iPr, nBu, Ph). In addition, the Pt(II) complex of the tertiary phosphine-stibine Acenap(PiPr2)(SbPh2) as well as the Mo(0) complex of Acenap(PiPr2)(SbMePh) were synthesised and characterised. Two of the phosphine-stibines and the two metal complexes were characterised by single-crystal X-ray diffraction. The peri-substituted species act as bidentate ligands through both P and Sb atoms, forming rather short Sb-metal bonds. The tertiary phosphine-stibines display through-space J(CP) couplings between the phosphorus atom and carbon atoms bonded directly to the Sb atom of up to 40 Hz. The sequestration of the P and Sb lone pairs results in much smaller corresponding J(CP) being observed in the metal complexes. QTAIM (Quantum Theory of Atoms in Molecules) and EDA-NOCV (Energy Decomposition Analysis employing Naturalised Orbitals for Chemical Valence) computational techniques were used to provide additional insight into a weak n(P)→σ*(Sb-C) intramolecular bonding interaction (pnictogen bond) in the phosphine-stibines. [ABSTRACT FROM AUTHOR]

Two new nickel(II) and cobalt(II) complexes, [Ni(MPAFA)3](BF4)2 (I) and [Co(MPAFA)3](BF4)2 (II) were synthesized from a pyrazole containing 'NN' bidentate Schiff-base ligand, N-(furan-2-ylmethyl)-1-(5-methyl-1H-pyrazol-3-yl)methanimine, (MPAFA) (L). The complexes I and II were characterized by various physico-chemical and spectral parameters. Both I and II were 1:3 (M:L) coordination complexes and behaving as 1:2 electrolytes. Single crystal X-ray diffraction studies revealed that both of them were distorted octahedral in nature with a N6 donor set. The binding interactions of the complexes with CT-DNA were studied by UV-Vis and fluorescence spectroscopic methods. I was found to bind with CT-DNA in a partial intercalative mode, whereas II bound via the groove-like manner in solutions. The ligand and the complexes were shown to have potential photocatalytic activity in degrading methylene-blue (MB) under UV-Vis light irradiation. [ABSTRACT FROM AUTHOR]

Environmentally acceptable and renewably sourced flame retardants are in demand. Recent studies have shown that the incorporation of the biopolymer lignin into a polymer can improve its ability to form a char layer upon heating to a high temperature. Char layer formation is a central component of flame-retardant activity. The covalent modification of lignin is an established technique that is being applied to the development of potential flame retardants. In this study, four novel modified lignins were prepared, and their char-forming abilities were assessed using thermogravimetric analysis. The lignin was obtained from date palm wood using a butanosolv pretreatment. The removal of the majority of the ester groups from this heavily acylated lignin was achieved via alkaline hydrolysis. The subsequent modification of the lignin involved the incorporation of an azide functional group and copper-catalysed azide–alkyne cycloaddition reactions. These reactions enabled novel organophosphorus heterocycles to be linked to the lignin. Our preliminary results suggest that the modified lignins had improved char-forming activity compared to the controls. 31P and HSQC NMR and small-molecule X-ray crystallography were used to analyse the prepared compounds and lignins. [ABSTRACT FROM AUTHOR]

The title dibromodisalicylaldehyde, obtained as a by-product in the m-chloroperoxybenzoic acid oxidation of 5-bromo-2-(methoxymethoxy)benzaldehyde, has been characterised by IR and NMR spectroscopy and X-ray diffraction. The structure features two independent molecules with a π–π stacking interaction between them. [ABSTRACT FROM AUTHOR]