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By introduction of trifluoromethyl and phenyl groups to 2-(2-thienyl)pyridine (thp), four new phosphorescent bis-cyclometalated iridium(III) complexes, (thp)2Ir(tpip), (cf3thp)2Ir(tpip), (cf3btp)2Ir(tpip) and (3-cf3btp)2Ir(tpip) (cf3thp = 2-(thiophen-2-yl)-4-(trifluoromethyl)pyridine, cf3btp = 2-(benzo[b]thiophen-2-yl)-4- (trifluoromethyl)pyridine, 3-cf3btp = 2-(benzo[b]thiophen-3-yl)-4-(trifluoromethyl)pyridine, tpip = tetraphenylimidodiphosphinate), were synthesized and fully characterized. The density functional theory and time-dependent DFT calculations show that the frontier orbitals are mainly localized in the Ir(III) ion and the cyclometalated ligands. Thus, the photophysical properties were dominated by the cyclometalated C∧N ligand, attributed to 3MLCT and 3ILCT transition. These Ir(III) complexes emit in the yellow-to-deep red region with photoluminescence quantum yields in the range 40.5–86.4% in CH2Cl2 solutions at 298 K. The organic light-emitting diodes (OLEDs) using (thp)2Ir(tpip), (cf3thp)2Ir(tpip) and (cf3btp)2Ir(tpip) as yellow, orange and deep red emitters display good electroluminescent performance with low efficiency roll-off. Notably, the device based on (cf3thp)2Ir(tpip) possesses very high EL efficiencies with the maximum luminance efficiency and external quantum efficiency (EQE) of 53.9 cd A−1 and 17.9%, respectively. Furthermore, the EQE for this complex could be still retained as 15.4% at a luminance of 1000 cd m−2.

Two new tfmpiq-based bis-cyclometalated iridium(III) complexes, [(tfmpiq) 2 Ir(imdzppo)] ( 2a ) and [(tfmpiq) 2 Ir(idzpo)] ( 2b ) (where tfmpiq = 1-(4-(trifluoromethyl)phenyl)isoquinoline, imdzppo = 2-(imidazo[1,2-a]pyridin-2-yl)phenol, idzpo = 2-(2 H -indazol-2-yl)phenol), have been synthesized and fully characterized. The single crystal structure of 2b has been determined. The relationship between the structures and photophysical properties of both complexes are considered, and the DFT calculations have been used to further support the deduction. These Ir(III) complexes emit red light with quantum yields of 39.9–51.9% in degassed CH 2 Cl 2 solution at room temperature. Also, their emission originates from a hybrid 3 MLCT/ 3 LLCT/ 3 LC excited state. All these results show that iridium(III) complexes 2a - 2b are suitable for red-phosphorescent materials in OLEDs.

Seven cyclometalated iridium(III) complexes Ir1–Ir7 based on phenylpyrazole derivatives as main ligands and tetraphenylimidodiphosphinate (tpip) as the ancillary ligand were synthesized and fully characterized. The proligands of 1-[4-(trifluoromethyl)phenyl]-1H-pyrazole (cf3ppz, 2a), substituted phenyl-2H-indazole {2-phenyl-2H-indazole (h-1-pidz, 2b), 2-(4-fluorophenyl)-2H-indazole (f-1-pidz, 2c), and 2-[4-(trifluoromethyl)phenyl]-2H-indazole (cf3-1-pidz, 2d)}, and substituted phenyl-1H-indazole {1-phenyl-1H-indazole (h-7-pidz, 2e), 1-(4-fluorophenyl)-1H-indazole (f-7-pidz, 2f), and 1-[4-(trifluoromethyl)phenyl]-1H-indazole (cf3-7-pidz, 2g)} were prepared with good yields. The emission maxima of all Ir(III) complexes can be tuned from 453 to 576 nm with different photoluminescence quantum yields (10.4–70.9%) by varying the type of substituent on the different main ligand frameworks. The organic light-emitting diodes using Ir(III) complexes as the emitters with blue, bluish-green, and yellow colors exhibit...

Nine new phosphorus-coordinated iridium(III) complexes of the form [Ir(C∧N)2(P∧P)]PF6, [Ir(F-piq)2(xantphos)]PF6 (1), [Ir(F-piq)2(binap)]PF6 (2), [Ir(F-piq)2(dppp)]PF6 (3), [Ir(Me-piq)2(xantphos)]PF6 (4), [Ir(Me-piq)2(binap)]PF6 (5), [Ir(Me-piq)2(dppp)]PF6 (6), [Ir(CF3O-piq)2(xantphos)]PF6 (7), [Ir(CF3O-piq)2(binap)]PF6 (8), and [Ir(CF3O-piq)2(dppp)]PF6 (9) (F-piq = 1-(4-fluorophenyl)isoquinoline, Me-piq = 1-(p-tolyl)isoquinoline, CF3O-piq = 1-(4-(trifluoromethoxy)phenyl)isoquinoline, xantphos = 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene, binap = 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl, dppp = 1,3-bis(diphenylphosphanyl)propane), have been synthesized and fully characterized. The crystal structures of 1, 7, and 9 have been determined by X-ray analysis. The most representative molecular orbital energy-level diagrams and the lowest energy electronic transitions of 1–9 have been calculated with density functional theory (DFT) and time-dependent DFT (TD-DFT). All of the complexes are orange-red emiss...

Three new phenylpropanoid derivatives, dasymaroacid A (1), dasymaroesters B and C (2 and 3), and one new polyoxygenated 6H-dibenzo[b,d]pyran-6-one derivative dasymarolactone D (4), together with seven known compounds (5-11), were isolated from the stems of Dasymaschalon rostratum Merr. Compounds 1 and 2 are unusual phenylpropanoid derivatives with a polymethyl substituted cyclopentene conjugated diketone as a substituent, and 3 is a unique cinnamic acid detective with a polymethyl substituted cyclohexene conjugated triketone as a substituent. Their structures were elucidated by extensive spectroscopic methods and chemical method, and 4 was further confirmed by the single crystal X-ray diffraction method. Compounds 1-4 and 7 showed weak anti-HIV-1 activities with EC50 values ranged from 16.44 to 25.91μM.

Two new meroterpenoids, penicianstinoids A and B (1 and 2), and eight new isocoumarins, peniciisocoumarins A-H (3-10), together with 10 known analogues (11-20) were obtained from the mangrove-derived fungus Penicillium sp. TGM112. The structures and absolute configurations of 1-10 were determined by interpretation of detailed NMR, MS spectroscopic data, X-ray diffraction analyses, modified Mosher's method, and calculated electronic circular dichroism data. Compounds 1-4, 7, 8, 10, 12, 13, and 16 showed growth inhibition activity against newly hatched larvae of Helicoverpa armigera Hubner with IC50 values ranging from 50 to 200 μg/mL, respectively. Compounds 1, 2, and 11-15 displayed activity against Caenorhabditis elegans with EC50 values ranging from 9.4 (± 1.0) to 38.2 (± 0.6) μg/mL, respectively. Compound 1 represents an austinoid-like meroterpenoid that is reported here for the second time, in which a carbon-carbon double bond was oxidized to a carbonyl group at C-1'-C-2'.

Four new cyclometalated bo-based iridium(III) complexes with different N^O ancillary ligands, [Ir(bo)2pic] (1), [Ir(bo)2prz] (2), [Ir(bo)2bop] (3) and [Ir(bo)2btp] (4) (bo = 2-phenylbenzo[d]oxazole, pic = picolinate, prz = pyrazinate, bop = 2-benzoxazol-2-yl phenol, btp = 2-benzothiazol-2-yl phenol), have been synthesized and investigated by optical spectroscopy, electrochemistry as well as density functional theory (DFT). The crystal structures of 1, 2 and 4 have been determined, which show that each adopts the distorted octahedral coordination geometry. They exhibit intense green to orange phosphorescence (λmax = 531–598 nm) with quantum yields of 0.19–0.94 and lifetimes of 0.078–0.468 μs in solution at 298 K. The broad range color tuning of complexes 1–4 is dependent on the ancillary ligand structure. The cyclic voltammetry has been measured, showing a quasireversible, metal-centered oxidation with potentials at 1.00–1.49 V. The frontier molecular orbital diagrams and the lowest-energy electronic transitions of 1–4 have been calculated with density functional theory (DFT) and time-dependent DFT (TD-DFT).

Two new fluorinated phenylisoquinoline-based iridium(III) complexes, [Ir(f2piq)2(bipy)][PF6] (3a) and [Ir(fmpiq)2(bipy)][PF6] (3b) (f2piq = 1-(2,4-difluorophenyl)isoquinoline, fmpiq = 1-(4-fluoro-2-methylphenyl)isoquinoline, bipy = 2,2′-bipyridine), have been synthesized and fully characterized. Single crystal X-ray diffraction study has been undertaken on complexes 3a and 3b, which show that each adopts the distorted octahedral coordination geometry with the cis-C,C′ and trans-N,N′ configuration. The photoluminescence spectra of 3a and 3b exhibit yellow and orange emission maxima at 584 and 600 nm, respectively. The frontier molecular orbital diagrams and the lowest-energy electronic transitions of 3a–3b have been calculated with density functional theory (DFT) and time-dependent DFT (TD-DFT). The absorption and emission spectra of complex 3b is red-shifted relative to those of complex 3a, as a consequence of the nature of the methyl group.

Six new pidz-based bis-cyclometalated Ir(III) complexes (Ir1-Ir6) have been synthesized and characterized. These complexes contain 2-phenyl-2H-indazole (pidz, 2a), 2-(4-fluorophenyl)–2H-indazole (fpidz, 2b), 2-(p-tolyl)–2H-indazole (ch3pidz, 2c), 2-(4-(trifluoromethyl)phenyl)–2H-indazole (cf3pidz, 2d), 2-(2,4-difluorophenyl)–2H-indazole (2,4-f2pidz, 2e) and 2-(3,5-difluorophenyl)–2H-indazole (3,5-f2pidz, 2f) as cyclometalated (C∧N) ligands, and acetylacetone (acacH) as ancillary ligand. The crystal structure of Ir2 has been determined by X-ray analysis. Different substituents of C∧N ligand in Ir2-Ir6 induce either a bathochromic or hypsochromic shift in the absorption spectra relative to the parent complex Ir1. The phenomenon is further well explained by DFT calculation and electrochemical study. All of the iridium(III) complexes are yellow emissive with quantum yields of 13.1–32.3% and lifetimes of 1.32–1.77 μs in solution at room temperature. We demonstrate that their emission originates from a hybrid 3MLCT/3ILCT/3LLCT excited state on the basis of the experimental and theoretical investigation. The corresponding yellow-emitting devices based on complexes Ir1, Ir2 and Ir4 can produce efficient electrophosphorescence with a luminance efficiency of 35.1–52.2 cd·A-1, a power efficiency of 20.8–32.1 lm·W−1 and an external quantum efficiency of up to 25.6%. All these EL data definitely suggest the bulky –CF3 skeleton in the doped materials could benefit the fabrication of high-efficiency phosphorescent OLEDs.

Four bis-cyclometalated iridium(iii) complexes, (bt)2Ir(tpip), (fbt)2Ir(tpip), (cf3bt)2Ir(tpip) and (dfbt)2Ir(tpip) (bt = 2-phenylbenzo[d]thiazole, fbt = 6-fluoro-2-phenylbenzo[d]thiazole, cf3bt = 2-phenyl-6-(trifluoromethyl)benzo[d]thiazole, dfbt = 5,7-difluoro-2-phenylbenzo[d]thiazole, tpip = tetraphenylimidodiphosphinate) have been synthesized and investigated. All complexes emit yellow light peaks at 564-574 nm with quantum efficiencies (Φem) of 27.1-48.4% and excited state lifetimes of 2.40-2.81 μs in degassed CH2Cl2 solution at room temperature. Correspondingly, organic light-emitting diodes (OLEDs) using these complexes as emitters achieve yellow electrophosphorescence with good device characteristics. Due to its highest photoluminescence quantum yield (48.4%), the device based on (dfbt)2Ir(tpip) displays the best device performance with a maximum current efficiency (ηc, max) of up to 69.8 cd A-1 and a maximum external quantum efficiency (EQEmax) of up to 24.3%. Furthermore, all devices showed low efficiency roll-off ratios. The EQE could still be retained at 17.7%, 16.4%, 18.3% and 20.6% for four devices at a luminance of 1000 cd m-2. These results suggest that these materials have potential application in efficient OLEDs.

Three new indole diterpenes, penicilindoles A–C (1–3), were isolated from the mangrove-derived fungus Eupenicillium sp. HJ002. Their planar structures and absolute configurations were determined by interpretation of NMR spectroscopic data, HR-ESIMS, and X-ray diffraction analysis using Cu Kα radiation. The cytotoxic and antibacterial activities were evaluated in vitro; penicilindole A (1) showed cytotoxic activity against human A549 and HepG2 cell lines with IC50 values of 5.5 and 1.5 μM, respectively.

A series of new cyclometalated btp-based iridium(III) complexes with three different ancillary ligands, Ir(btp)2(bozp) (3a), Ir(btp)2(btzp) (3b) and Ir(btp)2(izp) (3c) (btp = 2-(benzo[b]thiophen-2-yl)pyridine, bozp =2-(benzo[d]oxazol-2-yl)phenol, btzp =2-(benzo[d]thiazol-2-yl)phenol, izp = 2-(2 H-indazol-2-yl)phenol), have been synthesized and fully characterized. The crystal structure of 3b has been determined by single crystal X-ray diffraction analysis. A comparative study has been carried out for complexes 3a - 3c by UV-vis absorption spectroscopy, photoluminescence spectroscopy, cyclic voltammetry and DFT calculations. This observation illustrates that the substitution of N or S in ancillary ligand can lead to a marked bathochromic shift of absorption and emission wavelengths. The spectroscopic characterisation of these complexes has been complemented by DFT and TD-DFT calculations, supporting the assignment of (3)MLCT/(3)LC to the lowest energy excited state.

One new merosesquiterpenoid, craterellin D (1), along with one known analog, craterellin A (2), and five known ten-membered macrolides, 3-7, were isolated from a soft coral-derived Lophiostoma sp. fungus. The absolute configuration of 1 was established based on biogenetic consideration with the co-isolated analog 2, whose configuration was determined by modified Mosher's method and single-crystal X-ray diffraction analysis using CuKα radiation. The absolute configuration of 3 was determined by X-ray diffraction analysis using CuKα radiation. Compounds 2 and 3 showed antibacterial activities against Bacillus cereus with a MIC value of 3.12 μM.

A new bis-cyclometalated iridium(III) complex [Ir(dmabt)(2)(bipy)][PF(6)] (3) (dmabt = 4-(benzo[d]thiazol-2-yl)-N,N-dimethylaniline, bipy = 2,2'-bipyridine) has been synthesized and fully characterized. The complex 3 has been determined by X-ray structure analyses which shows that the central iridium(III) ion assumes distorted octahedral geometry. The photoluminescence spectrum exhibits orange emission maximum at 612 nm with quantum yield of 17% at 298 K. The frontier molecular orbital diagrams and the spin-allowed singlet-singlet electronic transitions of 3 have been calculated with density functional theory (DFT) and time-dependent DFT (TD-DFT), and the UV-Vis spectra are discussed based on the theoretical calculations.

A novel lumazine peptide, aspergilumamide A (1), as well as a known analog penilumamide (2), were isolated from the mycelia of a marine-derived fungus Aspergillus sp. (33241), obtained from the mangrove Bruguiera sexangula var. rhynchopetala collected from the South China Sea. The structure of 1 was identified by comprehensive spectroscopic analysis, including 1D- and 2D-NMR, ESI-MS, and MS/MS experiments. The absolute configuration of 1 was determined by Marfey's method.

Five new bis-cyclometalated iridium(III) complexes, [(bpbo)2Ir(acac)] (3a), [(fbpbo)2Ir(acac)] (3b), [(Mebpbo)2Ir(acac)] (3c), [(3,5-f2bpbo)2Ir(acac)] (3d) and [(2,4-f2bpbo)2Ir(acac)] (3e) (bpbo = 2-(biphenyl-4-yl)benzo[d]oxazole, fbpbo = 2-(4′-fluoro-[biphenyl]-4-yl)benzo[d]oxazole, Mebpbo = (4′-methyl-[biphenyl]-4-yl)benzo[d]oxazole, 3,5-f2bpbo = 2-(3′,5′-difluoro-[biphenyl]-4-yl)benzo[d]oxazole, 2,4-f2bpbo = 2-(2′,4′-difluoro-[biphenyl]-4-yl)benzo[d]oxazole, acac = acetylacetone), have been synthesized and fully characterized. A single crystal X-ray diffraction study was carried out on complexes 3a–3d, which showed that each adopted the distorted octahedral coordination geometry with the cis-C,C′ and trans-N,N′ arrangement. All Ir(III) complexes are luminescent (560–566 nm) with quantum yields of 3.6–53.5% and lifetimes of 0.282–0.382 μs in solution at 298 K. The spectroscopic and redox characterisation of these complexes were complemented by DFT and TD-DFT calculations, supporting the assignment of 3MLCT/LC to the emissive character.

Two CuI complexes based on the π-conjugated tetrathiafulvalene-annulated phenanthroline ligands (TTF-Phen, L1 and L2), [CuI(Xantphos)(L1)]BF4 (1, Xantphos = 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene) and [CuI(Binap)(L2)]BF4 (2, Binap = 2,2’-bis(diphenylphosphino)-1,1’-binaphthyl), have been synthesized. They have been fully characterized, and their photophysical and electrochemical properties are reported together with those of L1 and L2 for comparison. Both CuI complexes show metal-to-ligand charge transfer (MLCT) absorption bands, whereas the 3MLCT luminescence is strongly quenched.

Four new cyclometalated phenylisoquinoline-based iridium(III) complexes [Ir(C∧N)2(bipy)]PF6 (5a–5d) (bipy = 2,2′-bipyridine) have been synthesized and fully characterized, where the C∧N ligands are 1-(4-(trifluoromethyl)phenyl)isoquinoline, 4-(isoquinolin-1-yl)benzaldehyde, 4-(isoquinolin-1-yl)benzonitrile and 1-(3-fluoro-4-methylphenyl)isoquinoline, respectively. The crystal structures of 5a and 5c have been determined. The photophysical and electrochemical properties of these new complexes 5a–5d have been studied. All Ir(III) complexes exhibit orange phosphorescence in dichloromethane solution at room temperature with a maximum at 593–618 nm, quantum yield of 0.046–0.16. The frontier molecular orbital diagrams and the lowest-energy electronic transitions of 5a–5d have been calculated with density functional theory (DFT) and time-dependent DFT (TD-DFT).

Two new 1,3-dithiole derivatives, 4,4′-{9-[4,5-bis(methylthio)-1,3-dithiol-2-ylidene]-9H-fluorene-2,7-diyl} dipyridine(2a) and 3,3′-{9-[4,5-bis(methylthio)-1,3-dithiol-2-ylidene]-9H-fluorene-2,7-diyl} dipyridine(2b) were synthesized and characterized by Fourier transform infrared(FTIR), 1H NMR, 13C NMR and mass spectroscopies. The crystal structure of compound 2b was also studied. The optimized conformations and molecular orbital diagrams of compounds 2a and 2b were illustrated via density functional theory(DFT). By the time-dependent DFT(TD-DFT) method, electronic absorption spectra of compounds 2a and 2b were predicted and the results achieved were in good agreement with the experimental data. The formation of the cationic radical during the electrochemical oxidation process was also proposed.

A new iridium(III) complex based on the triazole-pyridine ligand with tetrathiafulvalene unit, [Ir(ppy) 2 ( L )]PF 6 ( 1 ), has been synthesized and structurally characterized. The absorption spectra, luminescent spectra and electrochemical behaviors of L and 1 have been investigated. Complex 1 is found to be emissive at room temperature with maxima at 481 and 510 nm. The broad and structured emission bands are suggested a mixing of 3 LC ( 3 π–π*) and 3 CT ( 3 MLCT) excited states. The influence of iridium ion coordination on the redox properties of the TTF has also been investigated by cyclic voltammetry.

One new merosesquiterpenoid, craterellin D (1), along with one known analog, craterellin A (2), and five known ten-membered macrolides, 3-7, were isolated from a soft coral-derived Lophiostoma sp. fungus. The absolute configuration of 1 was established based on biogenetic consideration with the co-isolated analog 2, whose configuration was determined by modified Mosher's method and single-crystal X-ray diffraction analysis using CuKα radiation. The absolute configuration of 3 was determined by X-ray diffraction analysis using CuKα radiation. Compounds 2 and 3 showed antibacterial activities against Bacillus cereus with a MIC value of 3.12 μM.

A quinoline-based colorimetric chemosensor (QDB) for Cu 2+ was synthesized by coupling quinoline-2-carbaldehyde with 4-(dimethylamino)benzohydrazide. Although most transition metal cations can cause redshifts in the UV–vis spectrum of QDB, the response of the chemosensor for Cu 2+ can be easily distinguished because it exhibits the largest redshift together with a color change from colorless to red in response to Cu 2+ . Other metal ions have no effect on the specific response of QDB to Cu 2+ . The significant redshift and color change were attributed to Cu 2+ -induced deprotonation of NH in the sensor.

A novel lumazine peptide, aspergilumamide A (1), as well as a known analog penilumamide (2), were isolated from the mycelia of a marine-derived fungus Aspergillus sp. (33241), obtained from the mangrove Bruguiera sexangula var. rhynchopetala collected from the South China Sea. The structure of 1 was identified by comprehensive spectroscopic analysis, including 1D- and 2D-NMR, ESI-MS, and MS/MS experiments. The absolute configuration of 1 was determined by Marfey's method.

A series of 1,3-dithiol-2-one derivatives via [4 + 2] Diels–Alder cycloaddition reaction of 4,5-bis(dibromomethyl)-1,3-dithiol-2-one with vinyl-substituted compounds have been synthesized. Structures of all the newly synthesized compounds are well supported by spectral data such as 1H-NMR, MS, and elemental analysis. The structures of IVf and IVg have been analyzed by X-ray crystallography.

Four new bis-cyclometalated iridium(III) complexes, [Ir(btq) 2phen] [PF6] (3a), [Ir(btq) 2bpy] [PF6] (3b), [Ir(btq) 2dtbipy] [PF6] (3c) and [Ir(btq) 2pic] (3d) (btq = 1-(benzo[b] thiophen-2-yl) isoquinoline, phen = 1,10-phenanthroline, bpy = 2,2′-bipyridine, dtbipy = 4,4′-di-tert-butyl-2,2′-bipyridine, pic = picolinic acid) have been synthesized and fully characterized. The crystal structure of 3a has been determined by X-ray analysis. The photophysical and electrochemical properties of these new complexes 3a − 3d have been studied. The photoluminescence spectra of all Ir(III) complexes exhibit deep-red emission maxima at 682, 682, 683 and 698 nm, respectively. The most representative molecular orbital energy-level diagrams and the lowest energy electronic transitions of 3a − 3d have been calculated with density functional theory (DFT) and time-dependent DFT (TD − DFT). The results show that the pic ancillary ligand of complex 3d influences the absorption and emission energies with a further red-shift relative to other three complexes 3a − 3c.

We report on the efficient removal of heavy metal ions and aromatic compounds from simulated wastewater with a nanocomposite. The nanocomposite was obtained via thermal decomposition of the precursor Fe(acac)3 onto the surface of graphene, modified by diethylenetriamine pentaacetic anhydride through dopamine. It was found that the maximum adsorption capacity of the nanocomposite toward Cu2+ and naphthalene was 207.9 and 72.2 mg g−1 respectively, displaying a high efficiency for the removal of heavy metal ions as well as aromatic compounds at pH 7.0 and 293 K. The Langmuir for naphthalene and the Freundlich for the Cu2+ adsorption isotherms were applicable for describing the removal processes. Furthermore, the nanocomposite was carefully examined by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, Raman spectra, and UV-vis spectroscopy. This work provides a very efficient, fast and convenient approach to exploring a promising nanocomposite for water treatment.

The asymmetric unit of the title compound, C22H23N5O2, contains two independent mol­ecules with similar conformations; the terminal pyridine rings are oriented at dihedral angles of 23.99 (8) and 18.07 (8)° with respect to the central benzene ring in one mol­ecule and 28.99 (8) and 23.22 (8)° in the other. In the crystal, N—H⋯O and weak C—H⋯O hydrogen bonds link the mol­ecules into a three-dimensional supra­molecular structure. Weak inter­molecular C—H⋯π inter­actions are also observed in the crystal.