Dalton Transactions

doi: 10.1039/b901775ppmid: N/A

doi: 10.1039/b901776npmid: N/A

doi: 10.1039/b901777cpmid: N/A

You, Youngmin; Park, Soo Young

doi: 10.1039/b812281dpmid: 19462644

Phosphorescent Ir(iii) complexes attract enormous attention because they allow highly efficient electrophosphorescence. In pursuing the development of Ir(iii) complexes during the last decade, significant progress has been made in terms of the colour-tunability, thermal- and photo-stability, phase homogeneity, and phosphorescence efficiency. By far, extensive synthetic efforts have been focused on the molecular design of ligands to achieve a wide range of phosphorescence colour that is compatible with organic light-emitting device (OLED) applications. In contrast, less has been known about a collective structure–property relationship for phosphorescence quantum efficiency. In fact, a few rule-of-thumbs for high phosphorescence quantum efficiency have been occasionally reported, but a collective rationale is yet to be investigated. In this article, we provide a comprehensive review of 8 different methods reported so far to achieve high phosphorescence quantum efficiency from Ir(iii) complexes. The methods included herein are limited to the cases of intramolecular controls, and thus are discussed in terms of variations in ligand structures: (1) geometric isomer control, (2) rigid structure and restricted intramolecular motion, (3) larger mixing of 1MLCT and 3LC states, (4) de-stabilizing a thermally accessible non-emissive state, (5) introducing dendrimer structures, (6) control in substituents of ligands, (7) confining the phosphorescent region of a mixed ligand Ir(iii) complex and (8) sensitized phosphorescence by using attached energy donors. Each method is closely related to intramolecular excited state interactions, which strongly affect radiative or non-radiative transitions. A comprehensive understanding of these methods leads us to conclude that the modulation in ligand structures has a profound effect on both the phosphorescence colour and phosphorescence quantum efficiency. Thus, the judicious selection of ligand structures and their chelate disposition should be considered before synthesis. We expect that the guidelines for attaining a high phosphorescence efficiency, summarized in this Perspective, would be helpful in developing highly phosphorescent Ir(iii) complexes.

Laird, Matthew F.; Pink, Maren; Tsvetkov, Nikolay P.; Fan, Hongjun; Caulton, Kenneth G.

doi: 10.1039/b822677fpmid: 19462645

The reaction of (PNP)NiH, where PNP is (tBu2PCH2SiMe2)2N−1, with CO2 occurs over a period of hours at 25 °C to form (POP)NiH(NCO), which involves transposition of the initial amide nitrogen and one oxygen of CO2.

Melero, Cristóbal; Guijarro, Albert; Yus, Miguel

doi: 10.1039/b821119cpmid: 19462646

The crystal structures of lithium naphthalene radical-anion (LiC10H8) and lithium naphthalene dianion (Li2C10H8) are reported, and their bonding properties analyzed.

Deng, Zhao-Peng; Zhu, Zhi-Biao; Gao, Shan; Huo, Li-Hua; Zhao, Hui

doi: 10.1039/b819705apmid: 19462647

The first continuous silver polyhedra framework containing four kinds of coordination spheres has been successfully prepared by the reaction of silver(I) nitrate and 4(1H)-pyridone-3-sulfonic acid. This polyhedra framework is constructed from four kinds of silver(I) polyhedra by sharing corners, edges and faces.

Gonzalez Calera, Silvia; Eisler, Dana J.; Goodman, Jonathan M.; McPartlin, Mary; Singh, Sanjay; Wright, Dominic S.

doi: 10.1039/b900268ppmid: 19462648

The in situ reaction of the dianion [OP(μ-NtBu)]22− with the dimer [ClP(μ-NtBu)]2 gives the O-bridged macrocycle [{P(μ-NtBu)}2(μ-O)]4 (1), being the largest crown-like phosph(iii)azane of its type to be reported and having a structure that is directly related to the ubiquitous 12-crown-4.

Dorson, Frédérick; Molard, Yann; Cordier, Stéphane; Fabre, Bruno; Efremova, Olga; Rondeau, David; Mironov, Yuri; Cîrcu, Viorel; Naumov, Nikolay; Perrin, Christiane

doi: 10.1039/b822105gpmid: 19462649

Zhao, Jun-Wei; Zheng, Shou-Tian; Li, Zhao-Hui; Yang, Guo-Yu

doi: 10.1039/b809338epmid: 19462650

A 65·8 CdSO4-type 3-D framework built by hexa-CuII sandwiched polyoxotungstates [Cu(en)2]2[Cu(deta)(H2O)]2[Cu6(en)2(H2O)2(B-α-GeW9O34)2]·6H2O (1) (en = ethylenediamine and deta = diethylenetriamine) has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrometry, thermogravimetric analysis and single-crystal X-ray diffraction. To the best of our knowledge, 1 represents the first 3-D TMSP with 65·8 CdSO4 topology in polyoxometalate chemistry. Magnetic measurements performed on 1 indicate the occurrence of ferromagnetic interactions within the copper ions and the coupling constants can be determined.