A carbazole functionalized mesoporous organic polymer (CzMOP) was synthesized by carbazolyl oxidative coupling polymerization. The nitrogen-rich CzMOP material was used as a good organic support for loading palladium nanoparticles to develop heterogeneous catalysts. The CzMOP and Pd nanoparticle supported MOP (Pd@CzMOP) was fully characterized using Brunauer–Emmett–Teller (BET) surface area analysis, X-ray diffraction analysis (XRD), Fourier transform infrared (FTIR) spectroscopy, solid-state 13C NMR spectroscopy, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). The Pd@CzMOP material exhibited excellent catalytic activity towards Suzuki–Miyaura cross coupling between aryl halides and phenyl boronic acid substrates. The catalytic system was found to be recycled up to five times without significant loss of catalytic activity.

•Four donor-acceptor structure isomers based on triphenylamine and acridine are synthesized.•Theoretical combined experimental characterizations are carried out for the excited state properties of the four isomers.•Substitution sites, twisted angles and conjugations make difference on the non-radiative rates.•Structure-property relationship of acridine based donor-acceptor molecules are further clarified for OLED applications.Charge-transfer (CT) state is becoming a useful excited state to design next-generation luminescence materials for high-performance organic light-emitting diode (OLED). However, strong CT state usually causes serious decrease in photoluminescence (PL) efficiency due to the small overlap between HOMO and LUMO. In order to harvest both high exciton utilization and high PL efficiency in fluorescent OLEDs, figuring out the strategy of fine modification of CT component in excited state through structural modulation is important. In this work, four donor–acceptor structure triphenylamine (TPA) - acridine (AC) isomers (TPA-9AC, TPA-1AC, TPA-2AC and TPA-3AC) were designed and synthesized to investigate structure-property relationship between isomerization effect and excited state properties. Density functional theory (DFT) calculations and solvatochromic absorption, emission and photoluminescence decay spectra are carried out for the deep understanding of their emissive state character. The four isomers exhibit gradually increased PL efficiency from low-polarity hexane to medium-polarity tetrahydrofuran (THF), which could be assigned to the formation of hybridized local and charge-transfer (HLCT) states and effectively suppressed non-radiative transition arised from acridine in medium-polarity solvents. Among four isomers, TPA-3AC achieved the best EL performance, due to the proper LE and CT compositions in the emissive state, demonstrating that isomerization of donor and acceptor functional moieties is an effective approach for structural modification for high-efficiency fluorescent OLED emitters.Download high-res image (210KB)Download full-size image

A concise and efficient method for the synthesis of a wide range of acridine derivatives and polycyclic aza-aromatic compounds from a ZnCl2-promoted cyclization reaction of readily available o-arylaminophenyl Schiff base compounds under convenient conditions was developed. Reaction conditions and scope of the new method were examined in detail.

•Three half-sandwich titanium aryloxides have been synthesized and characterized.•The molecular structure of complexes 4 and 6 has been determined.•Complexes 4–6 exhibit good catalytic activity for ethylene polymerization.Three bulky cyclopentadienyltitanium aryloxide complexes, [Ti(η5-C5Me4Ar)(O-2,6-tBu2C6H3)Cl2], (Ar = C6H5 (4), 4-iPrC6H4 (5), 4-Me3SiC6H4 (6)) have been synthesized from reaction of the corresponding cyclopentadienyltitanium trichloride derivatives with 1 equiv of LiO-2,6-tBu2C6H3. These half-sandwich complexes 4–6 have been characterized by 1H and 13C NMR spectroscopy. The molecular structure of complexes 4 and 6 has been determined by single-crystal X-ray diffraction studies. When activated with iBu3Al and Ph3C+B(C6F5)4−, complexes 4–6 exhibits reasonable catalytic activity for ethylene polymerization, producing moderate molecular weight polyethylenes.Three half-sandwich titanium complexes, (1-R-2,3,4,5-tetramethyl-cyclopentadienyl) (aryloxo)titanium dichloride complexes, [R = C6H5 (4), 4-iPrC6H4 (5), 4-Me3SiC6H4 (6); Ar = 2, 6-tBu2C6H3] were synthesized and structurally characterized. When activated with AliBu3 and Ph3C+B(C6F5)4−, complexes 4–6 exhibit reasonable catalytic activity for ethylene polymerization, producing moderate molecular weight polyethylene with high melting points.

The 7-amino-2,4-dimethylquinolinium salts with a variety of anions (Cl−, HCOO−, CH3COO−, PhCOO−, L-HOOCCH(OH)CH(OH)COO−) have been synthesized and characterized. The crystal structures of these salts were determined by single-crystal X-ray diffraction. The structure analysis confirms that the nitrogen atoms in the quinoline rings are protonated in all salts. The two solvates have been obtained and thereby provide a useful complement to cocrystal screening. All the quinolinium salts display interesting three dimensional supramolecular networks. The hydrogen bonding interactions observed in all of the salts are N–H⋯O, O–H⋯O and N–H⋯Cl, together with weak C–H⋯O, C–H⋯N, C–H⋯Cl hydrogen bonds. The weak C/N–H⋯π contacts and π–π stacking interactions involving the quinoline moieties also exist in quinolinium salts. The observed noncovalent interactions become prominent in stabilizing their crystal packing. The 7-amino-2,4-dimethylquinolinium salts show strong luminescence in the solid state and solution in the range 422–534 nm. The solid-state emission spectra of the quinolinium salts are sensitive to the anion species, and highly dependent on the nature of the stacking interactions.