We synthesized a series of CBP derivatives, using methyl groups as spatially demanding groups, locking the angle between the carbazole subunit and the biphenyl backbone as potential matrix material for blue organic light emitting diodes (OLEDs). The locked rotation was achieved by four methyl groups either in the 1,8-positions of the carbazole subunit (1) or in the 3,5,3',5'-positions of the biphenyl subunit (2) and the fixed spatial arrangement was confirmed by x-ray analysis. The physical properties of CBP derivatives based on the parent structure 2 were further tailored by electron withdrawing CF 3groups in 3,6-or 2,7-positions of the carbazole subunits (3 and 4) or alternatively by electron donating CH 3 O-groups in the 2,7-positions (5) of the same building blocks. Increased triplet energies (E T ) compared to the parent compound CBP were found for all synthesized CBP derivatives 1-5. Enhanced glass transition temperatures ranging between 129°C to 205°C further corroborate the application potential of these derivatives for matrix material in blue emitting OLEDs.

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and molecular electronics, [11,12] over medical diagnostic devices [13][14][15] to applications tuning macroscopic and/or environmental features like, e.g., the wettability [16][17][18] or the biocompatibility [19][20][21] of material surfaces. In most cases, a bifunctional molecule, combining an anchor group attaching the molecular compound to the surface with an exposed subunit representing the active moiety with tailored physiochemical properties is used to tune the surface's terminal appearance. While such approaches are successfully applied for entire objects and surfaces of considerable dimensions and macroscopic separations, there are limitations as soon as spatial patterns of varying surface functionalities and microscopic separations are desired or a spatially constrained surface-access including buried microfluidic chips has to be overcome. For example, conventional wet chemical surface functionalization procedures are spatially limited to the size of the droplet deposited (and its subsequent surface interaction) and methods depositing the molecules from gas-phase in vacuum require advanced masking strategies. Challenging are devices with a variety of molecular features to be created in a parallel process and in a locally controlled manner, like, e.g., multidimensional sensing platforms where a multitude of nearby molecular receptors are screening analytes in parallel. Or microfluidic chips with constrained access to functional sites as the channels are locally enclosed and inaccessible for droplet deposition. Of great interest are devices analyzing molecular binding events electronically, due to their miniaturization potential and the analyte-selective binding without the requirement of labels. In such devices, each electrode is electrically addressable in a separated manner as they were contacted individually. Such a preexisting electrical wiring scheme is a unique feature for an immobilization strategy able to distinguish between the applied electrical potentials of each electrode and a common electrolyte. The electrochemical release of thiol-based self-assembled monolayers (SAMs) on gold electrodes has been reported. [22] This allows the disintegration of existing SAMs. The subsequent decoration of the liberated electrode with an alternative thiol-molecule, however, is handicapped by scrambling with the remaining SAMs. Electrochemical triggered constructive build-up of molecular Local functionalization of surfaces is a current technological challenge. An electrochemically addressable alkyne protection group is presented enabling the site-selective liberation of alkynes exclusively on electrified electrodes. This controlled deprotection is based on a mendione chromophore which becomes a strong enough nucleophile upon reduction to intramolecularly attack the trialkylsilane alkyne protection group. The site-selective liberation of the alkyne is demonstrated by immobilizing the protected alkyne precursor on a transparent TiO 2 electrode and subsequently immobilizing red and blue azide dyes by azide-alky...

which suggested that either the cysteine was too large or disrupted substrate binding. Also F372C and N376C residues showed reduced chloride and rubidium affinity. The combined results of the two scanning approaches are consistent with our predictions of TM3 being an alpha helical domain with I368, G369, F372, A375, N376, A379 being pore lining residues.

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