Synthesis,X-ray crystal structure and photophysical properties of tris(dibenzoylmethanido)(1,10-phenanthroline)samarium(III)

Herein we report for the first time the complete characterization and photophysical properties of tris(dibenzoylmethanido)(1,10-phenanthroline)samarium(III) (Sm(DBM)₃phen) in the absence of a polymer matrix. The solid state structure of Sm(DBM)₃phen has been determined by single-crystal X-ray crystallography and shows the geometry of the local coordination environment around the samarium(III) ion to be a slightly distorted square antiprism. The absolute quantum yield and luminescence lifetime were measured as 0.86 ± 0.40% and 41 ± 2 μs, respectively.     

Synthesis and characterization of difunctional blue light-emitting molecules containing hole-transporting triphenylamino units

The synthesis of new difunctional (i.e., light-emitting and hole-transporting) fluorophore molecules, 2,2′-difuryl-4,4′-(N,N,N′,N′-tetraphenyl)diaminobiphenyl and 5,5′-bis(4-N,N′-diphenylaminophenyl)-2,2′-bifuryl, which contain hole-transporting triphenylamino units, are reported. These difunctional molecules emit intense blue photoluminescence and further reveal high HOMO energy values as well as high glass transition temperatures.     

Synthesis and optical properties of new chalcones containing 4-[bis(2-hydroxyethyl)amino]phenyl fragment

New chalcones with 4-[bis(2-hydroxyethyl)amino] phenyl fragment were obtained from 4-[bis(2-acetoxyethyl) amino]- benzaldehyde by the Claisen–Schmidt reaction. From their UV-VIS absorption and emission spectra, optical band gap values were calculated based on the Stokes shifts as well as the molar absorption coefficients and fluorescence quantum yields were estimated. The dependence of the absorption and emission maxima on solvent polarity and pH was evaluated.     

Highly strained tricyclic molecules: tricyclo[p.q.0.0]alkanes and phosphatricyclo[m.1.0.0]alkanes

We theoretically investigate ring strains of tricyclic molecules or tricyclo[p.q.0.0^1,f]alkanes by calculating the strain energies as heat of the homodesmotic reactions. The strain energies are well correlated with the deformation from the tetrahedral configuration of the C₁ atom. We theoretically design less strained tricyclic molecules by replacing some carbon atoms with phosphorus atoms.     

Synthesis and structure of tetrakis(isopropylimino)bis-[tris(dimethylamino)silylamino]alane

A novel cage-type compound tetrakis(isopropylimino)bis[tris(dimethylamino)silylamino]alane, H₆Al₆(NⁱPr)₄[NSi(NMe₂)₃]₂, (1), was prepared by reaction of tris(dimethylamino)silylamine H₂NSi(NMe₂)₃ with poly(isopropyliminoalane) (HAlNⁱPr)₆. The molecular structure of 1 was determined and discussed on the basis of FTIR, NMR and X-ray crystallographic analysis.     

Synthesis of E-alkenylsilanes with dithienosilole and their electrochemical and optical properties

A series of 2,6-bis(ethenylsilyl)-4,4-diphenyldithienosilole derivatives containing silylene-spacer were prepared by platinum-catalyzed hydrosilylation reaction. All the hydrosilylation proceeded regio- and stereoselectively to give solely β-(E)-adducts. The 2,6-bis(ethenylsilyl)-4,4-diphenyldithienosilole derivatives exhibit intense fluorescence emission and high quantum yields. The shoulder band of 9 in the emission spectrum was explained the intramolecular charge transfer from the electron-donating group (dimethylaminostyryl group) to electron-accepting group (dithienosilole moiety). These optical data are in good agreement with the results of theoretical calculations of model compounds at the level of B3LYP/6-31G(d,p).     

芳炔类共轭大环化合物

芳炔类大环化合物是最近10年来新兴的一种富碳共轭大环状分子，迅速发展到 近100种，可在光、电、磁、纳米等功能材料中得到广泛应用，引起了人们极大的 兴趣，对芳炔类大环化合物的研究，特别是合成方法和性质进行了综述，并提出了 这一领域的发展方向和需要解决的重点课题。     

Synthesis and photochromic properties of a dithia-dithienylethenophane

The thermally irreversible photochromic compound dithia-dithienylethenophane was synthesized, which is the first example of a dithienylethene bridged with benzene ring and due to the fixation to the photoactive anti-conformation the quantum yield for the photocyclization reaction became higher than that of the corresponding nonbridged type dithienylethene.     

Charge transport and optical properties of discotic liquid crystalline molecules THDDP and substituted THDP

The theoretical investigations have been carried out on the discotic liquid crystalline molecules, 2,3,6,7‐tetrakis‐hexyloxy‐9,16‐diaza‐dibenzo[a,c]phenazine (THDDP) and different substituted 2,3,6,7‐tetrakis‐hexyloxy‐dibenzo[a,c]phenazine (THDP) to study their charge transport and optical properties. The key parameters of charge transport such as charge transfer integrals and site energies have been calculated from the matrix elements of Kohn‐Sham Hamiltonian. The reorganization energy for the presence of excess charge and the rate of charge transfer calculated from Marcus theory have been used to find the mobility of the charge carrier in the studied molecules. The results show that the substitution and stacking angle change strongly affect the charge carrier mobility in π‐stacked THDDP and substituted THDP molecules. Molecular dynamics simulations have been performed to find the most favorable conformation. The time‐dependent density functional theory (TDDFT) calculations reveal that for these molecules the different substitutions does not alter the main features of optical properties and the molecules may be used as blue light emitters. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011     

Synthesis and optical behaviour of monodispersed oligo(fluorenylidene)s

The synthesis of the first series of monodispersed oligo(fluorenylidene)s is reported. The synthetic sequence envisages as key steps the obtainment (a) of a bis-pinacolboronate fluorenylidene dimer by a Ni(cod)₂ promoted homocoupling of the suitable 7-bromo-fluorenylidene boronic ester and (b) of the bis-pinacolboronate fluorenylidene trimer and tetramer by a Ni(cod)₂ promoted coupling of a 7-bromo-fluorenylidene boronic ester with 0.5 equiv of the corresponding 2,7-dibromofluorenylidene derivative. The optical properties of the obtained oligomers were studied. In the case of OF3 the optical behaviour was compared to that of a suitably synthesized fluorenone-containing model compound.     

Synthesis of aromatic polyethers by Scholl reaction. V. Synthesis and polymerization of 1,3-bis[4-(1-naphthoxy) benzoyl]benzene, 1,4-bis[4-(1-naphthoxy)benzoyl]benzene,bis[4-(1-naphthoxy)phenyl]methane, 1,3-bis[4-(1-naphthoxy) phenylmethyl]benzene,and 1,4-bis-[4-(1-naphthoxy)phenylmethyl]benzene

This article describes the synthesis and the cation-radical polymerization (Scholl reaction) of 1,3-bis[4-(1-naphthoxy) benzoyl] benzene ( 6 ) and 1,4-bis[4-(1-naphthoxy) benzoyl]- benzene ( 7 ) initiated by FeCI₃. This polymerization produced poly(ether ether ketone ketone)s (PEEKK) of number average molecular weight (M?_n) up to 5400 g/mol. The synthesis of bis[4-(1-naphthoxy) phenyl] methane ( 8 ), 1,3-bis[4-(1-napthoxy) phenylmethyl] benzene ( 9 ), and 1,4-bis[4-(1-naphthoxy) phenylmethyl] benzene ( 10 ) are also described. Polyethers of M?_n up to 15400 g/mol at a FeCl₃/monomer molar ratio of 2/1 were obtained. An increased polymerizability of the monomers 9 and 10 containing two CH₂ groups versus that of the corresponding monomers containing two carbonyl groups ( 6 and 7 ) was observed. This enhanced polymerizability was explained based on the increased nucleophilicity of monomers 9 and 10 .     

Synthesis and nonlinear optical properties of 1,3,5-methoxy-2,4,6-tris(styryl)benzene derivatives

[reaction: see text] Novel two-dimensional octupoles containing donors at the core and acceptors at the edge of peripheral groups were synthesized by Horner-Wittig reactions. These chromophores show very large first hyperpolarizability and good thermal stability and are attractive candidates for nonlinear optical materials.     

Ruthenium(II) complexes of 2-phenylimidazo[4,5-f] [1,10]phenanthroline. Synthesis,characterization and third order nonlinear optical properties

Three Ru^II complexes [Ru(bpy)₂(PIP)]²⁺, [Ru(PIP)₂(bpy)]²⁺ and [Ru(PIP)₃]²⁺ (PIP = 2-phenylimidazo[4,5-f][1,10]phenanthroline, bpy = 2,2-bipyridine) were prepared and characterized by electrospray mass spectrometry, ¹H-n.m.r, u.v.–vis. and electrochemistry. The nonlinear optical properties (NLO) of the Ru^II complexes were investigated by Z-scan techniques with 12 ns laser pulses at 540 nm, and all of them exhibit both NLO absorption and self-defocusing effects. The corresponding effective NLO susceptibility |³| of the complexes is in the (4.15 – 4.86) × 10^–12 e.s.u. range.     

Synthesis and physical properties of triptycene-based oligo(p-phenyleneethynylene)s

A series of symmetrical and unsymmetrical triptycene-based oligo(op-phenyleneethynylene)s were synthesized by deprotection of the acetone protected terminal alkynes, followed by Sonogashira coupling reactions. The photophysical properties of triptycene-based OPEs both in solution and solid state have been investigated by UV–Vis and fluorescence spectroscopy. Interestingly, the obtained compounds show strong fluorescence with partly high quantum yields in solid state, which suggested that triptycene moieties have not only prevented the intermolecular aggregation but also enforced the coplanarity of OPEs backbone in the solid state.     

Solvent effect on the complex formation of distally dialkylated calix[4]arenes with 1-chloro-4-(trifluoromethyl)benzene

The complexation behavior of the distally dialkylated calix[4]arenes and 4-tert-butylcalix[4]arenes (hosts) with 1-chloro-4-(trifluoromethyl)benzene (guest) was examined in four different alcohols (MeOH, EtOH, n-PrOH, n-BuOH) as solvents. The complex stability constants (K_s) and the complexation energy of the host-guest complexes were determined. Fair ‘by group’ linear correlations between each log K series determined in the same solvent and the complex stabilization energies were found. As a consequence, the solvents having high permittivities result in less stability of the host-guest complex in these particular cases examined.     

Synthesis, spectroscopic and nonlinear optical properties of multiple [60]fullerene-oligo(p-phenylene ethynylene) hybrids

A series of multiple [60]fullerene terminated oligo(p-phenylene ethynylene) (OPE) hybrid compounds has been synthesized through a newly developed in situ ethynylation method. Structural and magnetic shielding properties of the highly unsaturated carbon-rich C(60) and OPE scaffolds were characterized by 1D and 2D NMR spectroscopic analyses. Electronic interactions between the [60]fullerenes and the OPE backbones were investigated by UV/Vis spectroscopic and cyclic voltammetry (CV) experiments. Our studies clearly show that although the multiple [60]fullerene groups are connected via pi-conjugated OPE frameworks, they present diminutive electronic interactions in the ground state, and the electronic behavior of the [60]fullerene cages are only affected by the OPE backbones through modest inductive effects. Interestingly, sizable third-order nonlinear optical (NLO) responses (gamma) and enhanced two-photon absorption (TPA) cross-sections (sigma((2))) were determined for the multifullerene-OPE hybrid 31 relative to its OPE precursor from differential optical Kerr effect (DOKE) experiments. Such enhanced NLO performance is presumably due to the occurrence of periconjugation and/or charge transfer effects in the excited state. In addition, comparatively strong excited-state absorption was observed and characterized for OPE pentamer 12. Thus, the use of such fullerene-derivatized conjugated oligomers aids the quest for molecules with large third-order NLO and TPA properties.     

Theoretical study of structural and optical properties of regioregular head-to-tail oligo (3-n-octylthiophene) and related star molecules

The quantum chemical calculations of selected nonsubstituted or regioregular head-to-tail oligo (3-n-octylthiophene) and model thiophene–based star molecules using Density Functional Theory (DFT) are presented. The influence of the alkyl-substitution on the optimal geometries and relevant optical properties was analyzed. In the case of model star compounds, the presence of alkyl groups has a leading influence on structure as well as optical transitions. The Time Dependent DFT calculations of the vertically excited states show that the presence of alkyl group at the inner β-positions with respect to the phenylene central core is responsible for the generation of the low energy optical transitions with dominant oscillator strengths (over 0.25). The molecular orbital analysis of the lowest energy transition of the largest studied model star molecule (1,3,5-tris-(sexithienyl)-phenylene) also shows that the meta-conjugation in this zero-order dendrimer allows certain interactions among arms altogether.     

Synthesis of poly[1,1,1,3,3,3-hexafluoro-2-(pentafluorophenyl)propan-2-yl methacrylate]: Thermal and optical properties of the copolymers with methyl methacrylate

Poly[1,1,1,3,3,3-hexafluoro-2-(pentafluorophenyl)propan-2-yl methacrylate (I)] was synthesized, and the copolymers of the monomer I with various compositions of methyl methacrylate (MMA) were prepared and characterized. The glass transition temperature values obtained for the copolymers were between 120 and 150 °C. The refractive indices of the copolymers were in the range of 1.4350-1.4872 at 532 nm. They were thermally stable (up to 297-323 °C), and their water absorptive properties were greatly decreased, compared with pure PMMA.     

Reactions of [Fluoro(methylsulfonyloxy)iodo]benzene: II. Reaction of [Fluoro(sulfonyloxy)iodo]benzene with Acyclic Olefins

Reactions of [fluoro(sulfonyloxy)iodo]benzene with 1-hexene and 1-heptene smoothly yield the corresponding 1,2-disulfonates. Reaction of [fluoro(sulfonyloxy)iodo]benzenes with methyl methacrylate results in formation of isomeric -fluoro--sulfonyloxy products. A possible reaction mechanism is discussed.