The reaction of phosphole/arsole starting materials with a series of halide abstraction reagents afforded their respective phosphenium/arsenium complexes. UV-vis absorption and luminescence studies on these cations showed interesting emission profiles, which was found to be dependent upon counterion choice. The addition of a reductant to the phosphole reagent garnered a dimeric species with a central P-P bond, which when heated was found to undergo homolytic bond cleavage to produce an 11π radical complex. Electron paramagnetic resonance (EPR), supported by density functional theory (DFT) calculations, was used to characterize this radical species.

Continuous Stirred Tank Reactors (CSTRs) facilitate chemical manufacture in continuous flow and have been used for decades. They excel at solid handling and have well understood scale-up capacity. CSTRs in...

Luminescent transition metal complexes are introduced for the microcontact printing of optoelectronic devices. Novel ruthenium(II), RubpySS, osmium(II), OsbpySS, and cyclometalated iridium(III), IrbpySS, bipyridyl complexes with long spacers between the surface-active groups and the metal were developed to reduce the distance-dependent, nonradiative quenching pathways by the gold surface. Indeed, surface-immobilized RubpySS and IrbpySS display strong red and green luminescence, respectively, on planar gold surfaces with luminescence lifetimes of 210 ns (RubpySS·Au) and 130 and 12 ns (83%, 17%) (IrbpySS·Au). The modified surfaces show enhancement of their luminescence lifetime in comparison with solutions of the respective metal complexes, supporting the strong luminescence signal observed and introducing them as ideal inorganic probes for imaging applications. Through the technique of microcontact printing, complexes were assembled in patterns defined by the stamp. Images of the red and green patterns rendered by the RubpySS·Au and IrbpySS·Au monolayers were revealed by luminescence microscopy studies. The potential of the luminescent surfaces to respond to biomolecular recognition events is demonstrated by addition of the dominant blood-pool protein, bovine serum albumin (BSA). Upon treatment of the surface with a BSA solution, the RubpySS·Au and IrbpySS·Au monolayers display a large luminescence signal increase, which can be quantified by time-resolved measurements. The interaction of BSA was also demonstrated by surface plasmon resonance (SPR) studies of the surfaces and in solution by circular dichroism spectroscopy (CD). Overall, the assembly of arrays of designed coordination complexes using a simple and direct μ-contact printing method is demonstrated in this study and represents a general route toward the manufacture of micropatterned optoelectronic devices designed for sensing applications.

The functionalization of small diameter (ca. 50 nm) polycarboxylated nanodiamond particles using amide coupling methodologies in both water and acetonitrile solvent has been investigated. In this manner, the surfaces of nanodiamond particles were adorned with different luminescent moities, including a green fluorescent 1,8-naphthalimide moiety (Nap-1), and a red emitting ruthenium(II) tris-bipyridine complex (Ru-1), as well as dual functionalisation with both luminophores. Comprehensive characterization of the surface functionalized nanodiamonds has been achieved using a combination of dynamic light scattering, nanoparticle tracking analysis, transmission electron microscopy, X-ray photoelectron spectroscopy, zeta potential measurements, microwave plasma atomic emission spectroscopy and time-resolved photophysics. The tendency of the functionalized nanodiamonds to aggregate reflects the degree of surface substitution, yielding small aggregates with typical particle sizes ca. 150 nm. This is likely to be driven by the reduction of the zeta potential, concomitant with the conversion of surface charged carboxylate groups to neutral amide functions. The results show that luminescent nanodiamond materials can be synthesised with tuneable photophysical properties. 1

a Herein the first example of a bimetallic coiled coil featuring a lanthanide binding site is reported, opening opportunities to exploit the attractive NMR and photophysical properties of the lanthanides in multi metallo protein design. In our efforts to fully characterise the system we identified for the first time that lanthanide binding to such sites is pH dependent, with optimal binding at neutral pH, and that the double AsnAsp site is more versatile in this regard than the single Asp site. Our second site featured the structural HgCys 3 site, the chemistry of which was essentially unaltered by the presence of the lanthanide site. In fact, both metal binding sites within the hetero bimetallic coiled coil displayed the same properties as their mononuclear single binding site controls, and operated independently of each other. Finally, pH can be used as an external trigger to control the binding of Hg(II) and Tb(III) to the two distinct sites within this coiled coil, and offers the opportunity to "activate" metal binding sites within complex multi metallo and multi-functional designs.

A series of alkynyl aryl conjugated aldehydes and imines were prepared and their adducts with various Lewis acidic boranes have been studied via NMR, absorption, and luminescence spectroscopies in solution. The imine-B(C6F5)3 adduct showed remarkable solution stability, and was then trialled in vapochromism experiments using simple impregnated paper strips to examine the fluorescence responses.

No abstract

In the development of sensors based on multimodal detection, luminescent probes are attractive for providing a sensitive signal read-out, based either on intensity, wavelength shift or luminescence lifetime. The implicit simplicity of the devices that can be created is dependent of the judicious design of the multimodal probe. We have used transition metal probes which offer combined versatility due to their electroactive and photoluminescent properties, as well as their sensitivity to local environment. We report the influence of surfactant upon the formation of luminescent surfaces with metal complexes based on ruthenium(II), iridium(III) and osmium(II) bearing surface active groups. The results reveal an enhancement of the luminescence lifetime when a mixed monolayer with surfactant is formed. Characteristically, the luminescence lifetime of the ruthenium tris-bipyridyl complex attached to the gold surface increases from 210 ns to 765 ns in the presence of a fluorinated surfactant. The luminescence signal of the modified gold surfaces is also responsive to bovine serum albumin and fetal bovine serum adsorption, demonstrating interaction of the protein with the metal complex in the presence of the surfactant. The biomolecular interaction with the functionalised surfaces is also evidenced by surface plasmon resonance response.[a] Dr.