Metal-assisted salphen organic frameworks (MaSOFs) are known to possess high affinities to CO2 due to Lewis acidic metal sites and are therefore able to selectively adsorb CO2 over CH4 or N2. By aligning two metal centers in a carefully designed geometry, a “single molecular trap” (SMT) effect is generated, resulting in an interaction of two metal centers with one molecule CO2 by synergic effects. A condensation of a rigid triptycene based trissalicylaldehyde with tetrammino benzene is used to realize these metal alignments into MaSOFs. Characterization of the discrete trinuclear complexes proves that the chosen geometry is nearly optimal for synergic CO2 adsorption. The corresponding MaSOFs show high selectivities of CO2 against CH4 with a selectivity S IAST (according to the Ideal Adsorbed Solution Theory) of up to 13 and a selectivity of S IAST up to 70 against N2, which are also reflected by isosteric heat of adsorptions (Q st) of up to 35 kJ/mol. Density functional theory (DFT) calculations support the hypothesis by geometry optimized models and furthermore show a positive cooperative effect by an energy gain of ∼14 kJ/mol during the adsorption of CO2 in the second binding pocket of the trinuclear metal–salphen compared to a monomolecular adsorption.

This paper test card can identify ampicillin or amoxicillin formulations that contain <90% of the stated API content.

Molecular solar thermal (MOST) systems combine solar energy conversion, storage, and release in simple one‐photon one‐molecule processes. Here, we address the electrochemically triggered energy release from an azothiophene‐based MOST system by photoelectrochemical infrared reflection absorption spectroscopy (PEC‐IRRAS) and density functional theory (DFT). Specifically, the electrochemically triggered back‐reaction from the energy rich (Z)‐3‐cyanophenylazothiophene to its energy lean (E)‐isomer using highly oriented pyrolytic graphite (HOPG) as the working electrode was studied. Theory predicts that two reaction channels are accessible, an oxidative one (hole‐catalyzed) and a reductive one (electron‐catalyzed). Experimentally it was found that the photo‐isomer decomposes during hole‐catalyzed energy release. Electrochemically triggered back‐conversion was possible, however, through the electron‐catalyzed reaction channel. The reaction rate could be tuned by the electrode potential within two orders of magnitude. It was shown that the MOST system withstands 100 conversion cycles without detectable decomposition of the photoswitch. After 100 cycles, the photochemical conversion was still quantitative and the electrochemically triggered back‐reaction reached 94 % of the original conversion level.

You can′t separate this couple: One of the azo‐substituted tripycenes synthesized in this work is highlighted in front of its UV‐Vis absorption spectrum. Even though the azobenzenes are separated by a sp3 center, they experience excitonic coupling, as illustrated by the lightning. More information can be found in the Research Article by H. A. Wegner and co‐workers (DOI: 10.1002/chem.202200972). Design by Felix Bernt.

Molecular photoswitches are widely used in material sciences, physics, chemistry, and biology. As needs grow more complex, materials have to react more than one‐dimensionally. The use of multiple photoswitches at once opens manifold opportunities for further improved and more complicated systems. However, this requires independent addressability, i.e., orthogonality, and reversible processes. Herein, the first study on ultrafast excited state dynamics of two orthogonal photoswitches, a push‐pull azobenzene and a donor‐acceptor Stenhouse adduct is reported. In order to gain detailed insight in their interactions and mutual influences on their photoswitching behavior, they are addressed individually and simultaneously via transient absorption spectroscopy supported by quantum chemical calculations. They show reversible photoswitchability and in addition, can be used in 4D printing to provide easy access to a plethora of functional devices. Furthermore, environmental influences on the excited state dynamics are examined using different solvents and thin films. Both compounds photoisomerize independently when addressed individually or simultaneously and only little impacts on the excited state dynamics are found. Especially the vibrational relaxation is affected by different surroundings changing the energy dissipation while hardly affecting the electronic states involved. The orthogonal and simultaneous addressability is thereby crucial for their usage in 4D printed microactuators.

Herein, we report a series of azobenzene-substituted triptycenes. In their design, these switching units were placed in close proximity, but electronically separated by a sp 3 center. The azobenzene switches were prepared by Baeyer-Mills coupling as key step. The isomerization behavior was investigated by 1 H NMR spectroscopy, UV/Vis spectroscopy, and HPLC. It was shown that all azobenzene moieties are efficiently switchable. Despite the geometric decoupling of the chromophores, computational studies revealed exci-tonic coupling effects between the individual azobenzene units depending on the connectivity pattern due to the different transition dipole moments of the π!π* excitations. Transition probabilities for those excitations are slightly altered, which is also revealed in their absorption spectra. These insights provide new design parameters for combining multiple photoswitches in one molecule, which have high potential as energy or information storage systems, or, among others, in molecular machines and supramolecular chemistry.

A synthetic route to new gold(III) complexes was developed. From a [( tBu C ∧ N ∧ C)AuCl] complex as a precursor, a substitution by different azulene moieties was achieved. Because of the extraordinary photophysical properties of both substituted [(C ∧ N ∧ C)Au] compounds and azulene building blocks, the fusion of these generated organometallic azulene/gold(III) pincer hybrids. The isolated complexes were fully characterized and investigated, including X-ray single-crystal structure analysis, the electrochemical properties, and UV−vis spectra.