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Copper(I) complexes with thermal activated delayed fluorescence (TADF) have attracted considerable attention for the development of emissive materials in organic light-emitting devices. However, many emissive CuI complexes are cationic emitters and cannot be vacuum-sublimed, a process used for device fabrication. This has limited their applications in devices. In this work we have developed a series of emissive charge-neutral CuI complexes with the general formula [Cu(2,9- Me2phen)(CNR){CNB(C6F5)3}] [R = 2,6-Me2C6H3, 2,6-iPr2C6H3, 2,4,6-Cl3C6H2, 2,4,6-Br3C6H2, 3,5-(CF3)2C6H3, 4-SF5C6H4] through the incorporation of a strong p-accepting anionic isocyanoborate ligand. All the complexes have been structurally characterized and their photophysical properties have been studied. [ABSTRACT FROM AUTHOR]

Luminescent porous coordination polymers, cage-containing chains [Pb5(L1)6(N3)2(OH)2]n (1) and 1-D double helical chains [Pb(L2)(N3)]n (2) with 1-D channels were prepared by solvothermal reactions. These polymers can take up metal ions and induce different luminescence responses depending on the metal ions. [ABSTRACT FROM AUTHOR]

A new series of cyclometalated iridium(iii) complexes with isocyanoborate ligands [Ir(R2ppy)2(L)(CNBR′3)] (R = H or F; L = CNC6H4Cl-4 or PPh3; R′ = Ph, C6F5 or C6H4Cl-4), [Ir(biqb)(ppy)(CNBR′′3)] (R′′ = C6F5 or C6H4Cl-4) and {Ir(ppy)2(CN)n[CNB(C6F5)3]2−n}− (n = 0 or 1) have been synthesized and characterized. Three of these complexes have also been structurally characterized by X-ray crystallography. The photophysical and electrochemical properties of these complexes have been investigated. The effects of isocyanoborate ligands on the luminescence properties of these iridium(iii) complexes are also described. [ABSTRACT FROM AUTHOR]

A newclass of neutral bis(isocyanoborato) bis(bipyridyl)Os(II) complexes with the general formula of [Os(N–N)2(CNBR3)2] (N–N = bpy, 4,4′-Me2bpy; R = C6F5, C6H5) were prepared with simple synthetic methodologies. One of thesecomplexes was structurally characterized by X-ray crystallography.Unlike most of the neutral bis(bipyridyl) Os(II) complexes, whichare very weakly emissive or nonemissive, these isocyanoborato complexesdisplayed intense orange to red phosphorescence with a luminescentquantum yield up to 0.09 in CH2Cl2solutionat room temperature. The photophysical and electrochemical propertiesof these complexes were also investigated. Detailed photophysicalstudy showed that these complexes exhibited significantly enhancedemission properties over other reported neutral bis(bipyridyl) Os(II)complexes. In addition, it also revealed that the photophysics, electrochemistry,and excited state properties can be fine-tuned or modified throughthe functionalization of isocyanoborate ligands. [ABSTRACT FROM AUTHOR]

To improve the emission and excited-state properties of luminescent cyanometalates, new classes of highly solvatochromic luminescent cyanoruthenium(II) and cyanoruthenate(II) complexes of the general formulae [Ru(PR3)2(CN)2( $\widehat{NN}$)] and K[Ru(PR3)(CN)3( $\widehat{NN}$)], respectively, were developed. These complexes could be readily synthesized through the ligand-substitution reaction of K2[Ru(CN)4(PR3)2] with a diimine ligand. The geometrical isomerism of these complexes was characterized by using various spectroscopic techniques. Their photophysical properties, solvatochromism, and electrochemistry have also been investigated. Our detailed study showed that many of these complexes exhibited extremely environmentally sensitive emissions and significantly improved emission quantum efficiencies and lifetimes compared with the well-studied tetracyanoruthenate systems. [ABSTRACT FROM AUTHOR]

The development of molecular frameworks derived from binuclear platinum(II) aromatic Schiff base (salphen) complexes and their supramolecular chemistry have been undertaken. A series of axially rotating (Pt-salphen)2 luminophores, tethered in a cofacial manner by a rigid linker (xanthene, 1; dibenzofuran, 2; biphenylene, 3), was synthesized in which the O(salphen) groups are potentially amenable for guest-binding. The molecular structures of 1 and 3 have been determined by X-ray crystallography, revealing intra- and intermolecular π-stacking interactions, as well as contrasting syn ( 1) and anti ( 3) configurations, for the (Pt-salphen)2 moiety. All complexes are luminescent in solution at room temperature. Their photophysical and solvatochromic properties have been examined, and the emissions are assigned to mixed triplet O(p)/Pt(d)→π*(diimine) excited states. The red-shifted fluid emissions and lower quantum yields of 1 and 3, relative to 2, are ascribed to enhanced intramolecular π-stacking interactions. Photophysical changes and selective responses to metal ions (particularly Pb2+) have been investigated by using various spectroscopic methods and DFT calculations, and through comparative studies with control complexes. A plausible binding mechanism is proposed based on occupation of the O(salphen)-binding cavity, which induces perturbation of intramolecular π-π interactions, and hence the self-quenching and emission properties, of the (Pt-salphen)2 unit. [ABSTRACT FROM AUTHOR]

A series of rhenium complexes with acetylamino- and trifluoroacetylamino-containing 1,10-phenanthroline ligands have been synthesized, characterized and their photophysical and electrochemical properties studied. These complexes were found to show significant UV-vis and emission changes on addition of CN−, F−and AcO−anions. Their reactivity towards CN−, F−and AcO−anions, was also investigated by UV-vis, emission and 1H NMR spectroscopy. The reaction product between the trifluoroacetylamino-containing 1,10-phenanthroline ligand and the CN−anion has also been structurally characterized by X-ray crystallography. [ABSTRACT FROM AUTHOR]

A new series of diisocyanide-bridged homodinuclear Re(I) complexes [(phen)(L x )(CO) 2 Re(CNRNC)Re(CO) 2 (L x )(phen)] 2+ and their mononuclear analogues [Re(PPh 3 )(CNRNC)(CO) 2 (phen)] + [L x = CO and PPh 3 ; CNRNC = 1,4-phenylenediisocyanide (CNC 6 H 4 NC) and 4,4′-biphenyldiisocyanide (CNC 6 H 4 C 6 H 4 NC)] have been synthesized. The X-ray crystal structures of two of the dinuclear complexes were determined. The photophysics and electrochemistry of these complexes have been investigated. The dicarbonyl phosphino Re(I) phenanthroline complexes display intense MLCT [dπ(Re)→π ∗ (phen)] phosphorescence in CH 2 Cl 2 solution with luminescence quantum yield ( ϕ em ) in the range of 0.127–0.171. In contrast, the tricarbonyl dinuclear Re(I) complexes exhibit LC [π→π ∗ (phen)] phosphorescence with ϕ em from 0.0498 to 0.0625. [ABSTRACT FROM AUTHOR]

A series of luminescent rhenium(I) phenanthroline complexescontaining benzoxazol-2-ylidene ligands with the general formula {Re(CO)3(phen)[CN(X)C6H4-2-O]}+and cis,trans-{Re(CO)2(phen)(L)[CN(H)C6H4-2-O]}+(X = H, methyl; phen = 1,10-phenanthroline; L = PPh3, PPh2Me, P(OEt)3) have been synthesized andcharacterized. The X-ray crystal structures of most of the carbenecomplexes and some of their synthetic precursors have also been determined.A new synthetic methodology for the preparation of dicarbonyl rheniumdiimine synthetic precursors with a labile acetonitrile ligand, [Re(CO)2(phen)(PR3)(MeCN)]+, was developed.Photophysical study shows that these carbene complexes display a greento red 3MLLCT [dπ(Re) → π*(N–N)]phosphorescence at room temperature. The N-deprotonations of the benzoxazol-2-ylideneligand in these complexes were investigated. [ABSTRACT FROM AUTHOR]

Abstract: The rich excited state properties associated with the long-lived triplet metal-to-ligand charge transfer excited state of rhenium(I) tricarbonyl diimine complexes have been investigated for many years. Through judicious design and functionalization of the ligands with various functional moieties, these complexes can be used for different applications. However, further modification of the physical and excited state properties with their functions being maintained are challenging. In view of this, we have designed several new classes of isocyano rhenium(I) diimine complexes with readily tunable structural features. In this review article, our recent work on the syntheses, characterizations and photophysical properties of these tunable rhenium(I) diimine luminophores are discussed. [Copyright &y& Elsevier]