Because of similar properties and very low volatility, isomers of benzene poly(carboxylic acid)s (BPCAs) are very difficult to separate. In this work, we found that isomers of BPCAs could be separated efficiently by quaternary ammonium salts (QASs) via formation of deep eutectic solvents (DESs). Three kinds of QASs were used to separate the isomers of BPCAs, including the isomers of benzene tricarboxylic acids (trimellitic acid, trimesic acid, and hemimellitic acid) and the isomers of benzene dicarboxylic acids (phthalic acid and isophthalic acid). Among the QASs, tetraethylammonium chloride was found to have the best performance, which could completely separate BPCA isomers in methyl ethyl ketone solutions. It was found that the hydrogen bond forming between QAS and BPCA results in the selective separation of BPCA isomers. QAS in DES was regenerated effectively by the antisolvent method, and the regenerated QAS was reused four times with the same high efficiency.
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http://dx.doi.org/10.1021/jp5084136 | DOI Listing |
Chemistry
January 2025
Osaka Metropolitan University: Osaka Koritsu Daigaku, Chemistry, 3-3-138 Sugimoto, Sumiyoshi-ku, 558-8585, Osaka, JAPAN.
Gold(I)-catalyzed intramolecular hydroarylation of dialkynyl(biaryl)phosphine oxides provided versatile benzo-fused phosphepine oxides. O-exo adducts were obtained as the major product, and O-endo adducts were the minor product. O-exo and O-endo indicate the position of an oxygen atom with respect to the central phosphepine framework.
View Article and Find Full Text PDFActa Crystallogr C Struct Chem
February 2025
Institute of Applied Chemistry, Shanxi University, Wucheng, Taiyuan, Shanxi 030006, People's Republic of China.
Three bisferrocene-based bis(acylthiourea) positional isomers, namely, 1,2-bis(ferrocenylcarbonylthioureido)benzene (1), 1,3-bis(ferrocenylcarbonylthioureido)benzene (2) and 1,4-bis(ferrocenylcarbonylthioureido)benzene (3), all [Fe(CH)(CHNOS)], have been synthesized via facile nucleophilic addition reactions of 2.3 equivalents of ferrocenoyl isothiocyanate with o-, m- and p-phenylenediamine, respectively. The structures of the three new synthesized isomers were fully characterized by H NMR, C NMR, IR and UV-Vis spectroscopy, elemental analyses and cyclic voltammetry.
View Article and Find Full Text PDFChemistry
January 2025
The University of Electro-Communications: Denki Tsushin Daigaku, Department of Engineering Science, JAPAN.
(6,5)-enriched single-walled carbon nanotubes (SWCNTs) were reductively arylated using sodium naphthalenide and monosubstituted and disubstituted iodobenzene derivatives to control their photoluminescence (PL) properties. In the reactions with substituted iodobenzenes, the degree of functionalization was influenced by the substituents on the aryl groups depending on their position, which allowed us to realize control of the PL intensity. The substituents at the 2-position and methyl groups at the 3,5-positions of the phenyl group respectively increased the E11** PL and E11* PL selectivity at ~1230 and ~1100 nm.
View Article and Find Full Text PDFChemistry
January 2025
National Chi Nan University, Department of Applied Chemistry, TAIWAN.
Three fluorescent Zn coordaintion polymers (CPs) have been synthesized from the reactions of Zn(NO3)2∙6H2O, benzene-1,4-dicarboxylic acid (1,4-H2bdc), and angular carbazole-derived bispyridyl ligands (Cz-3,6-bpy or Cz-Pr-3,6-bpy). CPs 1-3 all adopt similar two-dimensional (2D) ring-and-rod layer structures, described as topologically 4-connected 2∙65 nets where the Zn(II) centers act as 4-connected nodes. CPs 1 and 2 are a pair of solvent-mediated supramolecular isomers where the former shows a two-fold interlocked 2D → 2D polyrotaxane-like entangled net and the latter reveals a four-fold interpenetrated 2D → 3D polyrotaxane entanglement.
View Article and Find Full Text PDFOrganometallics
January 2025
Department of Chemistry, Texas A&M University, 3255 TAMU, College Station, Texas 77842, United States.
Protolysis of AlMe or AlEt with 2-diisopropylphosphinopyrrole () resulted in alane/bis(phosphine) pincer ligands containing two flanking phosphines and a central Al-Me (), Al-Et () unit. Reactions of with [(COD)MI] (COD = 1,5-cyclooctadiene; M = Rh or Ir) in the presence of pyridine produced pincer complexes ( and ) with M supported by the PAlP tridentate ligand, and pyridine, methyl, and iodide as monodentate ligands for Al or M. The analogous reaction of with [(COD)MI] and pyridine resulted in the formation of the analogous compounds and with hydride in place of methyl.
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