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A series of gold acetonitrile complexes [Au(NCMe) ] [WCA] with weakly coordinating counterions (WCAs) was synthesized by the reaction of elemental gold and nitrosyl salts [NO] [WCA] in acetonitrile ([WCA] =[GaCl ] , [B(CF ) ] , [Al(OR ) ] ; R =C(CF ) ). In the crystal structures, the [Au(NCMe) ] units appeared as monomers, dimers, or chains. A clear correlation between the aurophilicity and the coordinating ability of counterions was observed, with more strongly coordinating WCAs leading to stronger aurophilic contacts (distances, C-N stretching frequencies of [Au(NCMe) ] units). An attempt to prepare [Au(L) ] units, even with less weakly basic solvents like CH Cl , led to decomposition of the [Al(OR ) ] anion and formation of [NO(CH Cl ) ] [F(Al(OR ) ) ] . All nitrosyl reagents [NO] [WCA] were generated according to an optimized procedure and were thoroughly characterized by Raman and NMR spectroscopy. Moreover, the to date unknown species [NO] [B(CF ) CN] was prepared. Its reaction with gold unexpectedly produced [Au(NCMe) ] [Au(NCB(CF ) ) ] , in which the cyanoborate counterion acts as an anionic ligand itself. Interestingly, the auroborate anion [Au(NCB(CF ) ) ] behaves as a weakly coordinating counterion, which becomes evident from the crystallographic data and the vibrational spectral characteristics of the [Au(NCMe) ] cation in this complex. Ligand exchange in the only room temperature stable salt of this series, [Au(NCMe) ] [Al(OR ) ] , is facile and, for example, [Au(PPh )(NCMe)] [Al(OR ) ] can be selectively generated. This reactivity opens the possibility to generate various [AuL L ] [Al(OR ) ] salts through consecutive ligand-exchange reactions that offer access to a huge variety of Au complexes for gold catalysis.

Optically coupled microcavities have emerged as photonic structures with promising properties for investigation of fundamental science as well as for applications. We report on the fabrication and spatially resolved spectroscopy of on-chip photonic molecule (PM) lasers consisting of two coupled, dye-doped polymeric microdisks on a silicon substrate. We investigate the fundamental lasing properties with focus on the spatial distribution of modes, the coupling dependent suppression of lasing modes, and in particular the application-oriented operation of these devices in aqueous environments. By depositing an additional polymer layer onto the lithographically structured cavities made of dye-doped poly(methyl methacrylate), coupling-gap widths below 150 nm with aspect ratios of the micro-/nanostructure exceeding 9 : 1 are achieved. This enables strong optical coupling at visible wavelengths despite relatively small resonator radii of 25 mm. The lasing properties of dye-doped PMs are investigated using spatially resolved micro-photoluminescence (m-PL) spectroscopy. This technique allows for the direct imaging of whispering-gallery modes (WGMs) in the photonics molecules. For subwavelength coupling gaps, we observe lasing from delocalized eigenstates of the PMs (termed in the following as super-modes). Using size-mismatched cavities, the lasing mode suppression for different coupling-gap widths is investigated. We further demonstrate single-mode lasing operation in aqueous environments with PMs, which are realized on a low-cost, polymer-on-silicon platform.

4-Hydroxy[2.2]paracyclophane is readily prepared via an improved synthetic protocol from unsubstituted [2.2]paracyclophane. The key step is a Dakin oxidation of 4-formyl[2.2]paracyclophane. This allows a rapid access to large quantities of the product and an easy synthesis of the enantiopure form.

To access the hitherto almost unknown class of clustered transition metal carbonyl cations, the trimetal dodecacarbonyls M3(CO)12 (M = Ru, Os) were reacted with the oxidant Ag+[WCA]−, but yielded the silver complexes [Ag{M3(CO)12}2]+[WCA]−...

A Hartwig-Buchwald addition of a variety of chiral amines to rac-4-bromo-[2.2]paracyclophane and rac-trifluoromethanesulfonic acid (4-[2.2]paracyclophane) ester was performed with high diastereoselectivities. Kinetic racemic resolution of the starting materials was achieved, providing a rapid access to enantiomerically enriched 4-bromo-[2.2]paracyclophane and the corresponding enantiomerically pure [2.2]paracyclophane amines. Additionally, the first reaction of a secondary amine with a [2.2]paracyclophane halide was achieved.

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A general synthetic strategy is described that enables access to a library of new sulfobetaine methacrylates starting from commercially available precursors. The three-step procedure allows the distance between the quaternary amine and the sulfonate group (inner charge distance) to be varied by selecting the corresponding dibromoalkane in the first step. A key step is the final esterification, in which methacrylic acid