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[Objectives] To identify the most suitable host plants for the development of Tetranychus urticae and Stethorus punctillum. [Methods] The developmental duration and fecundity of T. urticae, and the developmental duration, fecundity, hatching rate, pupation rate and eclosion rate of S. punctillum, were measured at a temperature of (25±1)°C and photoperiod of 14L : 10D, on different host plants. [Results] There were significant differences in the developmental duration of both species on different plants. The shortest developmental period of T. urticae was on peanut (9.82 d) and maximum fecundity of this species was recorded on peanuts and cowpeas. The developmental period of S. punctillum was shortest on peanut and cowpea (no significant difference), and highest on corn, peppers and eggplant. Fecundity of S. punctillum on the different banker plants was, peanut (112.60), cowpea (103.80), corn (85.20), pepper (68.20) and eggplant (53.40) and its adult eclosion rate on different banker plants was, peanut (80.11%), cowpea (70.26%), corn (66.66%), pepper (9.70%) and eggplant (29.81%). [Conclusion] Of the banker plants tested, peanut was the most suitable host for Tetranychus urticae and Stethorus punctillum. [ABSTRACT FROM AUTHOR]

A ruthenium-bis-terpyridine complex [Ru(NPhtpy)(Ntpy)]2+(22+) with two redox-asymmetricamine units has been prepared, where NPhtpy is 4′-(di-p-anisylaminophen-4-yl)-2,2′:6′,2″-terpyridineand Ntpy is 4′-(di-p-anisylamino)-2,2′:6′,2″-terpyridine.This complex displays two consecutive redox couples at +0.82 and +1.02V vs Ag/AgCl, which are assigned to the N•+/0processesof the amine components of the NPhtpy and Ntpy ligands, respectively.The mono-oxidized complex 23+obtained byoxidative electrolysis shows the presence of the charge transfer fromruthenium(II) to the oxidized aminium radical cation of the NPhtpyligand (MNNPhtpyCT) around 1000 nm. In the dioxidized form(24+), the MNNPhtpyCT transitiondecreased distinctly and an opposite charge transfer from ruthenium(II)to the oxidized aminium radical cation of the Ntpy ligand (MNNtpyCT) appeared at 1380 nm. Complexes [Ru(NPhtpy)(tpy)]2+(tpy is 2,2′:6′,2″-terpyridine), [Ru(Ntpy)(tpy)]2+, and [Ru(NPhtpy)2]2+have been preparedand studied for the purpose of comparison. TDDFT calculations showthat the involvement of the intraligand charge transfer from bothNPhtpy and Ntpy ligands is responsible for the enhancement of thevisible absorptions of these complexes with respect to [Ru(tpy)2]2+. DFT and TDDFT calculations have been performedon 23+and 24+toprovide information on the spin distributions and the nature of thenear-infrared absorptions. Complex 23+showsan isotropic EPR signal at room temperature, consistent with an unpairedelectron localized on the nitrogen atom. [ABSTRACT FROM AUTHOR]

Monoamine 1, diamines 2-4, triamine 5, and tetraamine 6 have been synthesized by substituting dianisylamino groups at the 1-, 3-, 6-, and/or 8-positions of pyrene. Diamines 2-4 differ in the positions of the amine substituents. No pyrene-pyrene interactions are evident in the single-crystal packing of 3, 4, and 6. With increasing numbers of amine substituents, the first oxidation potential decreases progressively from the mono- to the tetraamine. These compounds show intense charge-transfer (CT) emission in CH2 Cl2 at around 530 nm with quantum yields of 48-68 %. Upon stepwise oxidation by electrolysis or chemical oxidation, these compounds were transformed into radical cations 1(⋅+) -6(⋅+) and dications 2(2+) -6(2+) , which feature strong visible and near-infrared absorptions. Time-dependent density functional theory studies suggested the presence of localized transitions from the pyrene radical cation and aminium radical cation, intervalence CT, and CT between the pyrene and amine moieties. Spectroscopic studies indicated that these radical cations and dications have good stability. Triamine 5 and tetraamine 6 formed efficient CT complexes with tetracyanoquinodimethane in solution. The results of EPR spectroscopy and density functional theory calculations suggested that the dications 2(2+) -4(2+) have a triplet ground state, whereas 5(2+) and 6(2+) have a singlet ground state. The dication of 1,3-disubstituted diamine 4 exhibits a strong EPR signal., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Nine cyclometalated ruthenium complexes with a redox-active diphenylamine unit in the para position to the RuC bond were prepared. MeO, Me, and Cl substituents on the diphenylamine unit and three types of auxiliary ligands-bis(N-methylbenzimidazolyl)pyridine (Mebip), 2,2':6',2''-terpyridine (tpy), and trimethyl-4,4',4''-tricarboxylate-2,2':6',2''-terpyridine (Me3 tctpy)--were used to vary the electronic properties of these complexes. The derivative with an MeO-substituted amine unit and Me3 tctpy ligand was studied by single-crystal X-ray analysis. All complexes display two well-separated redox waves in the potential region of +0.1 to +1.0 V versus Ag/AgCl, and the potential splitting ranges from 360 to 510 mV. Spectroelectrochemical measurements show that these complexes display electrochromism at low potentials and intense near-infrared (NIR) absorptions. In the one-electron oxidized form, the complex with the Cl-substituted amine unit and Mebip ligand shows a moderate ligand-to-metal charge transfer at 800 nm. The other eight complexes show asymmetric, narrow, and intense intervalence charge-transfer transitions in the NIR region, which are independent of the polarity of the solvent. The Mebip-containing complexes display rhombic or broad isotropic EPR signals, whereas the other seven complexes show relatively narrow isotropic EPR signals. In addition, DFT and time-dependent DFT studies were performed to gain insights into the spin distributions and NIR absorptions., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Two series of linear ruthenium coordination oligomers, [(Ntpy)Ru(n)(tppz)(n-1)(tpy)](2n+) (mono-Ntpy series, n = 1-3) and [(Ntpy)2Ru(n)(tppz)(n-1)](2n+) (bis-Ntpy series, n = 1-3) have been prepared, where Ntpy is the capping ligand 4'-di-p-anisylamino-2,2':6',2''-terpyridine, tppz is tetra-2-pyridylpyrazine, and tpy is 2,2':6',2''-terpyridine. The electrochemical measurements evidence oxidation events from both the amine segments and the metal centers and reduction waves from tppz and the capping ligands. Both series complexes display much enhanced light absorption with respect to model complexes without terminal amine units. Density functional theory (DFT) calculations have been performed on both series and time-dependent DFT (TD-DFT) calculations have been performed on the bis-Ntpy-series compounds (n = 1-4) to characterize their electronic structures and excited states and predict the electronic properties of long-chain polymers. Upon one-electron oxidation, the mono-Ntpy-series monoruthenium and diruthenium complexes display N(+)-localized transitions and metal-to-nitrogen charge-transfer (MNCT) transitions in the near-infrared (NIR) region. DFT and TD-DFT computations on the one-electron-oxidized forms of the mono-Ntpy-series compounds (n = 1-4) provide insight into the nature of the MNCT transitions and the degree of charge delocalization., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Electron delocalization of new mixed-valent (MV) systems with the aid of lateral metal chelation is reported. 2,2'-Bipyridine (bpy) derivatives with one or two appended di-p-anisylamino groups on the 5,5'-positions and a coordinated [Ru(bpy)(2)] (bpy = 2,2'-bipyridine), [Re(CO)(3)Cl], or [Ir(ppy)(2)] (ppy = 2-phenylpyridine) component were prepared. The single-crystal molecular structure of the bis-amine ligand without metal chelation is presented. The electronic properties of these complexes were studied and compared by electrochemical and spectroscopic techniques and DFT/TDDFT calculations. Compounds with two di-p-anisylamino groups were oxidized by a chemical or electrochemical method and monitored by near-infrared (NIR) absorption spectral changes. Marcus-Hush analysis of the resulting intervalence charge-transfer transitions indicated that electron coupling of these mixed-valent systems is enhanced by metal chelation and that the iridium complex has the largest coupling. TDDFT calculations were employed to interpret the NIR transitions of these MV systems., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)