Synthesis, characterization and properties of nicotinamide and isonicotinamide complexes with diverse dicarboxylic acids

Optimizing Nickel(II) Complex Catalysts for High-Yield Oligomerization of Cyclohexyl Isocyanide

Isocyanides, due to the divalent carbon atom present in their structure, are among the most reactive groups of compounds in organic chemistry. Unfortunately, although according to the literature they do not have acute toxicity, they have a very unpleasant odor that makes it difficult to collaborate with them. However, despite the properties mentioned, reactions of isocyanides often lead to a variety of functional materials. In this article, we present a modified method for obtaining isocyanide-based polymers that significantly reduce the release of their hazardous vapors into the environment. For the study, a series of nickel(II) metal ion complex compounds containing organic ligands (e.g., 2,2'-bipyridyl, 1,10-phenanthroline, and diglycolate anion) were synthesized and used as catalysts in the oligomerization reaction of cyclohexyl isocyanide. The obtained oligomers were subjected to quantitative and qualitative physicochemical analyses (FT-IR, MALDI-TOF-MS, TGA/DSC, and DSC), which confirmed their structure and thermal properties. Reaction yields ranged from moderate (8-52%) to extremely high (94%) for a single catalyst. The synthesized catalytic systems are new, previously undescribed isocyanide oligomerization catalysts, which successfully led to the synthesis of poly(cyclohexyl isocyanide) and allowed us to obtain materials that can be used to produce many useful polymeric materials.

Stereoselective synthesis and X-ray structure determination of novel 1,2-dihydroquinolinehydrazonopropanoate derivatives

A novel series of 1,2-dihydroquinolinhydrazonopropanoate have been synthesized via a convenient aza-Michael addition reaction between hydrazinylquinolinones and ethyl propiolate in ethanol under refluxing temperature. The structures for all obtained products were confirmed with FTIR, NMR spectrums, as well as mass spectrometry. In addition, the monoclinic structure for compounds 8a, 8c, and 8d was also confirmed via X-ray crystallography analyses. The E-configuration for the obtained products was confirmed form the X-ray analysis. On the other hand, the crystal packing shows that the intermolecular and hydrogen bonds between atoms are parallel to the bc plan.

Different effects in the selective detection of aniline and Fe3+ by lanthanide-based coordination polymers containing multiple reactive sites

Isostructural Ln-CPs (1-Eu and 2-Tb) show almost the same high detection ability for Fe³⁺ and different detection abilities for aniline. The detection difference was studied through PXRD, UV-vis, luminescence lifetimes and Hirshfeld surface analysis.

Isonicotinamide-Based Compounds: From Cocrystal to Polymer

The reaction between [Cu(μ-OAc)(μ-Pip)(MeOH)]₂ (1) (OAc = acetate; Pip = 1,3-benzodioxole-5-carboxylate) and isonicotinamide (Isn) in MeOH as solvent yielded two mixture pairs of three compounds: {(HPip)₂(Isn) (2), [Cu(Pip)₂(Isn)₂] (3)} and {(3), {[Cu₃(Pip)₂(OAc)₂(μ-Isn)₂(Isn)₂(μ-OCH₃)₂(MeOH)₂]·2MeOH}_n (4)}. Modifying the reaction conditions (t, T, molar ratio), 2 and 3 have been successfully isolated, whereas 3 and 4 had to be mechanically separated. The recrystallization of 3 in pentanol yielded single crystals of compound [Cu(Pip)₂(Isn)₂]·C₅H₁₁OH (3a). The X-ray crystal structure of 2, 3a, and 4 has been elucidated showing a cocrystal, a monomer, and an unusual coordination polymer, respectively. The Pip ligand exhibited a chelate (3a) or a monodentate (4) coordination mode, but the Isonicotinamide (Isn) ligand is the one that promoted the arrangement of different structures and also mainly directs the formation of the 2D and 3D supramolecular assemblies. All the structures have been analyzed by Hirshfeld surface. In addition, the energy frameworks and lattice energy values of 2 and 3a have been calculated.

Ammonium 2,2'-thiodiacetates - Selective and environmentally safe herbicides

2,2'-Thiodiacetic acid derivatives have a wide application potential, mainly in coordination chemistry. This research indicates that quaternary ammonium 2,2'-thiodiacetate salts may also be potent herbicidal agents used in agriculture. To provide a rationale for this statement, the toxic effect by a alkyl and aryl quaternary ammonium salts (QASs) on plant growth was investigated. The phytotoxicity of these compounds was tested against cultivated monocotyledonous (spring barley) and dicotyledonous (common radish) plants, whereas herbicidal activity was investigated in relation to popular weeds species (white goosefoot, sorrel and gallant-soldier). The results showed that aliphatic QASs possessed a low phytotoxicity to food crops and that some of them (in particular triethylammonium salt) had potent and selective herbicidal properties against common weeds, such as sorrel and gallant-soldier. However, the investigated compounds appeared to be ineffective herbicides against white goosefoot.

An influence of structural changes in ammonium cations on ecotoxicity of 2,2'-thiodiacetate mono and bis-salts

2,2'-Thiodiacetates with their excellent complexing properties may be used as metal extraction agents, fluorescent and superparamagnetic materials, antibacterial and anticancer medical agents, however there are no data concerning the environmental impact of 2,2'-thiodiacetates derivatives and data definying the potential hazard connected with their use. This study describes the ecotoxicity assessment of seven 2,2'-thiodiacetates with non-metallic, alkyl and aryl ammonium cations, which were obtained in an environmentally friendly, solvent-free syntheses. The ecotoxicity of these water soluble compounds was tested in aquatic and benthic environments using luminescent marine bacteria Vibrio fischeri (Microtox^® test) and the crustaceans Heterocypris incongruens (Ostracodtoxkit F™), respectively. The antimicrobial and antifungal activity against Trichoderma viridis, Aspergillus niger, Rhizoctonia solani and Escherichia coli was also investigated. The results showed how structural changes within ammonium cations themselves influence ecotoxicity: the QASs with alkylammonium cations exhibited a similar, rather low toxicity both to Vibrio fischeri and Heterocypris incongruens, and they would not pose a risk to these organisms in case of leakage. Higher toxicity was observed in case of two isoquinolinium salts, however it was rather associated with the heteroaromatic cation, than with the 2,2'-thiodiacetate anion.