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Synthetic access to a five (hetero)arene ring-fused 3-phenyl[1,2,4]triazines is described. The resulting compounds were characterized via 1H and 13C NMR, IR, UV–vis spectroscopy and HRMS. The structure of 3-phenyl[1,2,4]triazino[5,6-c]quinoline was unambiguously confirmed by single crystal XRD. [ABSTRACT FROM AUTHOR]

[closo-B10H8-1,10-(COOH)2]2− was obtained in five steps and 40% overall yield from [closo-B10H10]2−. It can be converted to [closo-B10H8-1,10-(CO)2] and subsequently to carbonium ylides [closo-B10H8-1-COOH-10-(C(NRCH2)2)]. The diacid, its derivatives, and di-ylide [closo-B10H8-1,10-(C(NHMe)2)2] are characterized by spectroscopic and single crystal XRD methods augmented with DFT results. [ABSTRACT FROM AUTHOR]

C(1)‐vinylation of [closo‐1‐CB9H10]− (A) and [closo‐1‐CB11H12]− (B) with 4‐benzyloxystyryl iodide followed by hydrogenation of the double bond and reductive deprotection of the phenol functionality led to C(1)‐(4‐hydroxyphenethyl) derivatives. The phenol functionality was protected as the acetate. The esters were then treated with PhI(OAc)2 and the resulting isomers were separated kinetically (for derivatives of anion A) or by chromatography (for derivatives of anion B) giving the difunctionalized building blocks in overall yields of 9 % and 50 %, respectively. A similar series of reactions was performed starting with anions A and B and 4‐methoxystyryl bromide and iodide. Significant differences in the reactivity of derivatives of the two carborane anions were rationalized with DFT computational results. Application of the difunctionalized carboranes as building blocks was demonstrated through preparation of two ionic liquid crystals. The extensive synthetic work is accompanied by single crystal XRD analysis of six derivatives. [ABSTRACT FROM AUTHOR]

Derivatives [closo‐B10H8‐1,10‐(CN)2]2– and [closo‐B10H8‐1,10‐(OCHNMe2)2], efficiently obtained from [closo‐B10H8‐1,10‐(IPh)2] by nucleophilic substitution with CN– and DMF, were envisioned as precursors to diacid [closo‐B10H8‐1,10‐(COOH)2]2– and to dihydroxy derivative [closo‐B10H8‐1,10‐(OH)2]2–, respectively. Attempts at hydrolysis or reduction of the dinitrile gave no reaction or complex mixtures of products. In contrast, the DMF adduct was cleanly hydrolyzed to diformate [closo‐B10H8‐1,10‐(OCHO)2]2– and subsequently to protonated dihydroxy [closo‐B10H8‐1,10‐(OH2)2]. The latter was O‐acylated with PhCOCl. Crystal and molecular structures of five derivatives were established by single crystal XRD methods and compared to those for other [closo‐B10H8‐1,10‐X2]2– derivatives. Trends in molecular geometry in the series and also reactivity of the dinitrile and intermediates were corroborated and correlated with DFT results (B3LYP/TZVP) by analysis of bonding, charge distribution and vibrational frequencies. [ABSTRACT FROM AUTHOR]

Two novel mixed ligand complexes with general formula [M2(4,4′-bpy)1.5(CBr2HCOO)6(H2O)2]n (where 4,4′-bpy = 4,4′-bipyridine) were synthesized. Thermal analysis was used to describe a solid intermediate and final products of thermolysis. A coupled TG-MS system was used to monitor principal volatile fragments evolved during pyrolysis. Crystal structures of the complexes were determined. Cationic dinuclear M2 (M(III) = La, Sm) coordination cores were obtained. Both crystal structures are isostructural. Single crystal X-ray diffraction analysis revealed that investigated structures of 1D coordination polymers assembled in ladder-like systems. The central atom replacement resulted in unit cell identity parameter П = 0.0091. Additionally, the isostructurality of the reported La(III) and Sm(III) complexes was revealed using Hirshfeld Surface analysis supported by Enrichment Ratio calculations. [ABSTRACT FROM AUTHOR]

Five complexes of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) with non-steroidal anti-inflammatory drug, flufenamic acid were synthesized: (1) [Mn3(fluf)6EtOH)(H2O)]·3EtOH; (2) [Co(fluf)2(EtOH)(H2O)]·H2O; (3) [Ni(fluf)2(EtOH)(H2O)]·H2O; (4) [Cu(fluf)2·H2O]; (5) [Zn(fluf)2·H2O]. All complexes were characterized by elemental analysis (EA), flame atomic absorption spectrometry (FAAS), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The crystal structure of 1 was determined by the single crystal X-ray diffraction technique. It crystallizes in the triclinic space group P 1 ¯ with three independent Mn(II) cations, six coordinated flufenamato ligands augmented with water and ethanol molecules in the inner coordination sphere. In this crystal, manganese atoms are multiplied by symmetry and form infinite, polymeric chains which extend along the [001] dimension. The Hirshfeld Surface analysis revealed changes in interaction assemblies around all metal centers. The antioxidant and antimicrobial activities were established for all complexes and free ligand for comparison. All compounds exhibit good or moderate bioactivity against Gram-positive bacteria and yeasts. [ABSTRACT FROM AUTHOR]

Three metal complexes of mefenamato ligand 1 were synthesized: [Co2(mef)4(EtOH)2(H2O)4]: 2; [Co(mef)2(MeOH)4]∙2MeOH: 3; and [Ni(mef)2(MeOH)4]∙2MeOH: 4. Their compositions and properties were investigated by elemental analysis (EA), flame atomic absorption spectrometry (FAAS), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). Crystal structures were determined by the single crystal X-ray diffraction technique. Additionally, their antioxidant and antimicrobial activity were established, thus proving good/moderate bioactivity against Gram-positive bacteria and yeasts. In the crystal structure of 2, an apical water molecule is shared between two adjacent cobalt(II) ions, resulting in the formation of a polymeric chain extending along the [100] direction. Meanwhile, structures 3 and 4 have strong intermolecular hydrogen bonds with diverse topologies that yield unique quasi-isostructural arrangements. The packing topology is reflected by the Hirshfeld surface analysis of intermolecular contacts. [ABSTRACT FROM AUTHOR]

Two metal complexes of theophylline were synthesized. Namely, 1 with the formula [Cu(theop)2(H2O)3]·2H2O and 2, [Zn(theop)2]∙H2O (where: theop = theophylline ion). Their properties were thoroughly investigated by the elemental analysis (EA), flame atomic absorption spectrometry (FAAS), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) that were augmented by antimicrobial and antioxidant analyses. Their radical scavenging ability (RSA) is notably higher than that of a pure theophylline itself. Similarly to theophylline complexes already studied by us 3, [Mn(theop)2(H2O)4] 4, [Co(theop)2(H2O)4] and 5, [Ni(theop)2(H2O)4] title compounds are inactive against Gram-negative bacteria, but they show moderate or mild activity against Gram-positive rods. The low temperature, single crystal X-ray diffraction technique determines the crystal structure of 1. Its supramolecular crystal topology is affected by the unique, double palindrome water chain that formed by two conserved and a sole coordinated water molecules. Crystal packing arrangements were characterized by fingerprint plots that were derived from the Hirshfeld surfaces (HS), as calculated for all structures in the series 1, 3, 4, 5. [ABSTRACT FROM AUTHOR]