Metallo-cryptophane cages from cis-linked and trans-linked strategies.

Data supporting study of Pd(II) metallo-cage species from cyclotriguaiacylene derived ligands

Multimodal Radio- (PET / SPECT) and Fluorescence Imaging Agents Based on Metallo-Radioisotopes: Current Applications and Prospects for Development of New Agents

This perspective focuses on complexes of radioactive metal ions applied in multimodal radio- and optical imaging. The application of metal ions in radioimaging techniques such as Positron Emission Tomography (PET) and Single Photon Emission Computed Tomography (SPECT) has advantages over lighter nuclei in terms of half-life, but there are particular issues related to their speciation (particularly leaching from complexes) and with the combination of certain ions with fluorescent systems. The basic coordination chemistry of the ions involved and issues relating to biological conditions and their compatibility with optical imaging techniques are reviewed, the current literature presented in context, and the prospect of exploiting the intrinsic luminescence of certain metal–ligand complexes is discussed

Application of d6 transition metal complexes in fluorescence cell imaging

Luminescent d(6) transition metal complexes have often been proposed as useful fluorophores for cell imaging due to their attractive photophysical attributes, but until very recently their actual applications have been scarce, and largely limited to ruthenium complexes in DNA and oxygen sensing. In the last few years, however, there has been an increasing number of reports of the design and application in cellular studies of a diverse range of Ir, Re and Ru complexes tailor-made for imaging applications. The design principles, uptake and cellular localisation of this new class of imaging agents are presented in context in this feature article

Organometallic complexes of transition metals in luminescent cell imaging applications

Recent developments in the application of organometallic complexes in cell imaging are reviewed, along with the fundamental requirements for a cell imaging agent, highlighting the contribution which organometallic chemistry can make in this area

Experimental and theoretical characterisation of phosphorescence from rhenium polypyridyl tricarbonyl complexes

Synthetic, spectroscopic and theoretical methods are used to probe the photophysics of five rhenium polypyridyl tricarbonyl complexes, which exhibit strong phosphorescence behaviour. Particular focus is placed on the effect of polypyridyl ligand structure on absorption and emission properties, for instance by extending conjugation or by addition of electron donating groups. Experimental methods are performed in a consistent and controlled manner, thereby giving data that is ideally suited for comparison with theory. Modifications in ligand structure give rise to large changes in absorption energies, but rather smaller differences in emission. Density functional theory (DFT) and its time-dependent formulation (TD-DFT) perform rather better in predicting emission than absorption. The effect of environment on photo-physical properties was probed theoretically by protonating nitrogen(s) of dipyrido[3,2-a:2′,3′-c]phenazine. (dppz) This has a large effect on calculated spectra and leads to more complex patterns of absorption and emission that require spin-orbit coupling to be included in DFT calculations for full explanation

Tris(rhenium fac-tricarbonyl) Polypyridine Functionalized Cyclotriguaiacylene Ligands with Rich and Varied Emission

Trinuclear rhenium fac-tricarbonyl bromide complexes have been synthesized coordinated to the host ligands tris(4-[4-methyl-2,2′-bipyridyl]methyl)cyclotriguaiacylene (L1), tris(4-[4-methyl-2,2′-bipyridoyl])cyclotriguaiacylene (L2), and tris(4-[2,2′,6′,2″-terpyridyl]benzyl)cyclotriguaiacylene (L3). The structure of L1 and complexes [{Re(CO)3Br}3(L1)] (1) and [{Re(CO)3Br}3(L3)] (3) have been elucidated through X-ray single-crystal diffraction, with complex 3 crystallizing as a conglomerate. The steady-state luminescent properties and time-resolved fluorescence studies of the complexes have been conducted and revealed an unusual dual-emission phenomenon for complex 2. Complexes 1 and 2 show red-shifted emission wavelengths in comparison with those typical of monometallic Re(CO)3-bipy-Br complexes, while complex 3 showed an unusual excitation-dependent variation of emission wavelength

The importance of cellular localisation of probes: synthesis, photophysical properties, DNA interactions and cellular imaging properties of rhenium dppz complexes with known cellular localisation vectors.

The synthesis, photophysical properties, DNA binding, DNA cleavage and cellular imaging behaviour of a range of complexes of the type [Re(CO)3(dppz)(PyR)]+ are reported, where PyR represents a range of substituted pyridines which have previously been studied for cellular localisation of related complexes. Confocal imaging experiments confirm that the complexes retain the variety of cellular localisation behaviour associated with the PyR units in other complexes, and suggest applications as probes for oligonucleotides in specific cellular compartments (e.g. mitochondrial DNA). This study illustrates the importance of considering cellular localisation as a prime consideration in the design of probes for in vivo application

Three-Dimensional Silver-dabco Coordination Polymers with Zeolitic or Three-Connected Topology

The simple linear linking ligand diazabicyclo­[2.2.2]­octane (dabco) combines with silver­(I) to form three-dimensional (3D) coordination polymers which have either a zeolitic <b>mtn</b> topology structure or a (10,3)-b <b>ths</b> network according to the counteranion used. The tetrahedral anions BF₄^– or ReO₄^– promote formation of [Ag­(dabco)₂]·X, which has a 3D four-connected <b>mtn</b> framework of fused 5¹² and 6⁴5¹² cages, and the material shows modest absorption of iodine. The bulky anion [Co­(C₂B₉H₁₁)₂]⁻ and an excess of dabco promote formation of complex [Ag₂(dabco)₃­(CH₃CN)₂]­·2­[Co­(C₂B₉H₁₁)₂] with a three-connected (10,3)-b network, while use of 1 equiv of dabco gives a previously reported [Ag­(dabco)]­·[Co­(C₂B₉H₁₁)₂], which has a one-dimensional coordination chain structure

Syntheses, structural studies and spectroscopic characterisation of pyridyl–phthalimide complexes of fac-(CO)3ReI-diimines

The mono-dentate ligands, 3-aminomethyl-N-phthalimido-pyridine (L1) and 3-amino-N-phthalimido-pyridine (L2), were synthesised using a solvent-free melt method. These ligands were then used to access three pairs of functionalised luminescent ReI complexes of the generic type fac-{Re(CO)3(diimine)(Ln)}(BF4). The photophysical studies show that the visible emission from each of the six complexes is 3MLCT at room temperature. Within each pair of complexes the precise energy of the emission was subtly dependent upon the axial ligand, Ln with luminescence lifetimes in the range 121–288 ns