The title Schiff base, C(27)H(33)N(7), is a tripodal amine displaying C(3) symmetry, with the central tertiary N atom lying on the threefold crystallographic axis. The N-CH(2)-CH(2)-N conformation of the pendant arms is gauche [torsion angle = 76.1 (3)°], which results in a claw-like mol-ecule, with the terminal aniline groups wrapped around the symmetry axis. The lone pair of the apical N atom is clearly oriented inwards towards the cavity, and should thus be chemically inactive. The amine NH(2) substituents lie in the plane of the benzene ring to which they are bonded. With such an arrangement, one amine H atom forms an S(6) motif through a weak N-H⋯N hydrogen bond with the imine N atom, while the other is engaged in an inter-molecular N-H⋯π contact involving the benzene ring of a neighbouring mol-ecule related by inversion. The benzene rings also participate in an intra-molecular C-H⋯π contact of similar strength. In the crystal structure, mol-ecules are separated by empty voids (ca 5% of the crystal volume), although the crystal seems to be unsolvated.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3011466 | PMC |
http://dx.doi.org/10.1107/S1600536810043783 | DOI Listing |
Chemistry
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 PDFPhys Chem Chem Phys
January 2025
Key Laboratory of Soft Chemistry and Functional Materials of MOE, School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China.
2-(2-Hydroxyphenyl)benzothiazole (HBT) derivatives with donor-π-acceptor (D-π-A) structure have received extensive attention as a class of excited state intramolecular proton transfer (ESIPT) compounds in the fields of biochemistry and photochemistry. The effects of electron-donors (triphenylamine and anthracenyl), the position of substituents and solvent polarity on the fluorescence properties and ESIPT mechanisms of HBT derivatives were investigated through time-dependent density functional theory (TDDFT) calculations. Potential energy curves (PECs) and frontier molecular orbitals (FMOs) reveal that the introduction of the triphenylamine group on the benzene ring enhances intramolecular HB, thereby benefiting the ESIPT process.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Donghu Experimental Station of Lake Ecosystems, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, PR China; Southwest United Graduate School, Kunming 650092, PR China. Electronic address:
Cyanobacteria blooms are concerning due to algal toxins like microcystin-leucine arginine (MC-LR). Despite progress in detecting MC-LR and understanding its toxic effects, including calf thymus DNA (CT-DNA) damage, the mechanisms for fluorescent probe detection of MC-LR and its binding to CT-DNA are poorly understood. In this study, we designed three fluorescent probes for MC-LR detection.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Department of Chemistry, The Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and Reconstruction, Division of Life Science, State Key Laboratory of Molecular Neuroscience, and Department of Chemical & Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China.
The two contradictory entities in nature often follow the principle of unity of opposites, leading to optimal overall performance. Particularly, aggregation-induced emission luminogens (AIEgens) with donor-acceptor (D-A) structures exhibit tunable optical properties and versatile functionalities, offering significant potential to revolutionize cancer treatment. However, trapped by low molar absorptivity (ε) owing to the distorted configurations, the ceilings of their photon-harvesting capability and the corresponding phototheranostic performance still fall short.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!