1024915-91-0Relevant articles and documents
A Crystalline Three-Dimensional Covalent Organic Framework with Flexible Building Blocks
Liu, Xiaoling,Li, Jian,Gui, Bo,Lin, Guiqing,Fu, Qiang,Yin, Sheng,Liu, Xuefen,Sun, Junliang,Wang, Cheng
, p. 2123 - 2129 (2021)
The construction of three-dimensional covalent organic frameworks (3D COFs) has proven to be very challenging, as their synthetic driving force mainly comes from the formation of covalent bonds. To facilitate the synthesis, rigid building blocks are always the first choice for designing 3D COFs. In principle, it should be very appealing to construct 3D COFs from flexible building blocks, but there are some obstacles blocking the development of such systems, especially for the designed synthesis and structure determination. Herein, we reported a novel highly crystalline 3D COF (FCOF-5) with flexible C-O single bonds in the building block backbone. By merging 17 continuous rotation electron diffraction data sets, we successfully determined the crystal structure of FCOF-5 to be a 6-fold interpenetrated pts topology. Interestingly, FCOF-5 is flexible and can undergo reversible expansion/contraction upon vapor adsorption/desorption, indicating a breathing motion. Moreover, a smart soft polymer composite film with FCOF-5 was fabricated, which can show a reversible vapor-triggered shape transformation. Therefore, 3D COFs constructed from flexible building blocks can exhibit interesting breathing behavior, and finally, a totally new type of soft porous crystals made of pure organic framework was announced.
Synthesis of novel bis- and poly(hydrazinylthiazole) linked to benzofuran or benzothiazole as new hybrid molecules
Salem, Mostafa E.,Darweesh, Ahmed F.,Shaaban, Mohamed R.,Elwahy, Ahmed H.M.
, p. 73 - 88 (2019)
A novel series of bis- and poly(thiazoles) substituted with benzofuran and benzothiazole moieties were prepared in good yields by the reaction of the appropriate bis(α-bromoketones) with the corresponding bis- and poly(hydrazinecarbothioamide) in refluxing EtOH in the presence of TEA. The structures of the new compounds were confirmed based on elemental analyses as well as spectral data.
Two star-shaped tetranuclear Ru(II) complexes containing uncoordinated imidazole groups: Synthesis, characterization, photophysical and pH sensing properties
Cheng, Feixiang,Yu, Shiwen,He, Chixian,Ren, Mingli,Yin, Hongju
, p. 712 - 721 (2016)
Tetrapodal ligands H4L1 and H4L2 containing imidazole groups have been synthesized by the reaction of 1,10-phenanthroline-5,6-dione with 1,2,4,5-tetrakis[(4-formylphenoxy)methyl]benzene and 1,2,4,5-tetrakis[(3-formylphenoxy)methyl]benzene, respectively, in presence of NH4OAc. Two star-shaped complexes [{Ru(bpy)2}4(μ4-H4L1)](PF6)8 and [{Ru(bpy)2}4(μ4-H4L2)](PF6)8 (bpy = 2,2′-bipyridine) have been prepared by refluxing Ru(bpy)2Cl2·2H2O and each ligand in ethylene glycol. The deprotonated complexes [{Ru(bpy)2}4(μ4-L1)](PF6)4 and [{Ru(bpy)2}4(μ4-L2)](PF6)4 have been obtained by the reaction of sodium methoxide with [{Ru(bpy)2}4(μ4-H4L1)](PF6)8 and [{Ru(bpy)2}4(μ4-H4L2)](PF6)8, respectively, in methanol. The pH effects on the UV-vis light absorption and emission spectra of both complexes have been studied, and ground- and excited-state ionization constants of both complexes have been derived. The photophysical properties of both complexes are strongly dependent on the solution pH. They act as proton-induced off-on-off luminescent sensors through two successive deprotonation processes of imidazole groups, with a maximum on-off ratio of 8 in buffer solution at room temperature. Theoretical calculations for the highest occupied molecular orbital (HOMO) and lowest occupied molecular orbital (LOMO) orbitals of bridging ligand are also presented for plausible explanations of the fluorescence changes.
Synthesis and Structures of Novel Multi-armed Molecules Involving Benzene as a Core and 4-Phenylthiazole, 4-Pyrazolylthiazole, or Thiadiazole Units as Arms
Salem, Mostafa E.,Darweesh, Ahmed F.,Farag, Ahmad M.,Elwahy, Ahmed H. M.
, p. 586 - 595 (2017/02/03)
A synthesis of novel three-, four-, and sixfold branched 4-phenylthiazolylhydrazones, 4-pyrazolylthiazolyl hydrazones, and thiadiazoles which are linked to a benzene core via phenoxymethyl spacers was reported. The synthetic methodology includes initially formation of poly(aldehyde thiosemicarbazones) 9, 14, and 15 by acid catalyzed condensation of thiosemicarbazide (8) with the appropriate poly(aldehydes) 3, 5, and 7, respectively. Subsequent reaction of 9, 14, and 15 with each of 2-bromo-1-phenylethanone (10a) and 2-bromo-1-(4-chlorophenyl)ethanone (10b) in refluxing ethanol in the presence of few drops of TEA afforded 11, 16, and 18, respectively, in good yields. On the other hand, the synthesis of the novel poly(4,5-dihydro-1,3,4-thiadiazolyl) derivatives 20, 21a,21b, and 22 was performed by cyclization of 9b, 14a,14b, and 15a, respectively, in refluxing acetic anhydride.
Synthesis and characterization of poly(2,6-dimethyl-4-phenyl-1,4-dihydropyridinyl)arenes as novel multi-armed molecules
Abdelhamid, Ismail A.,Darweesh, Ahmed F.,Elwahy, Ahmed H.M.
, p. 7085 - 7088 (2015/12/01)
A new series of poly(2,6-dimethyl-4-phenyl-1,4-dihydropyridinyl)arenes were synthesized in good yields using a one-pot, acid-catalyzed cyclocondensation reaction of the appropriate poly(aldehydes) with 3-aminobut-2-enenitrile in acetic acid at reflux.
Synthesis and characterization of new organic phosphonates monomers as flame retardant additives for polymers
Finocchiaro, Paolo,Consiglio, Giuseppe A.,Imbrogiano, Andrea,Failla, Salvatore
, p. 1689 - 1701 (2008/02/11)
Commercially available polyphenols react with diethylphosphite to give polyphosphonates, which are easily transformed by LDA in good yields to polyorthohydroxy aryl phosphonates. Moreover, some bis-benzyl aminobenzyl phosphonates have been prepared in good yields. These new monomers are of great relevance for the synthesis of thermal resistant polycondensates containing phosphonate moieties.
