Metal‐free triazole turns : 1,5‐Disubstituted peptidyl triazoles are obtained regioselectively from the 1,3‐dipolar cycloaddition of peptidyl phosphoranes and azides. Peptide turns are thus formed that contain a conformationally locked cis peptide bond. Being regioselective and free of heavy metals, this reaction may find broad application in chemical biology and medicinal chemistry.
Fruity electrodes : A simple bottom‐up self‐assembly method was used to fabricate rambutan‐like tin–carbon (Sn@C) nanoarchitecture (see scheme, green Sn) to improve the reversible storage of lithium in tin. The mechanism of the growth of the pear‐like hairs is explored.
Calculating cyclization : Theoretical work directed towards the elucidation of the mechanisms of the gold‐, palladium‐, and lanthanum‐catalyzed oxycyclizations (5‐exo versus 6‐endo versus 7‐endo) of γ‐allenols has been pursued in close relationship with the experimental study (Part 1, accompanying paper) and has corroborated the bench results to provide a complete study of the reactivity of γ‐allenols under different metal‐catalyzed conditions.
Selective HCOOH decomposition to H 2 /CO 2 on Au : Au species catalyze HCOOH dehydrogenation at higher rates than on Pt, previously considered the most active metal. Dehydrogenation occurs through formate decomposition limited by H2 desorption on Au species undetectable by TEM. CO did not form (<10 ppm), making products suitable for low‐temperature fuel cells.
Supramolecular chirality and liquid crystalline OFET : Achiral end‐capped oligothiophenes can be tuned to exhibit supramolecular chirality with unique striped textures showing distinct circular dichroism signals as well as a highly ordered SmE phase that leads to high hole carrier mobility.
Losing the grip : The synthesis of multivalent low‐molecular‐weight dendrons with lysine branching units coupled to disulfide‐linked spermine surface groups is described. It is furthermore demonstrated that the dendrons bind DNA with good affinity (see image), but are also able to release the DNA in a reductive environment.
The fiveway junction : The synthesis of ligands with five symmetrically diverging binding sites is described and their assembly into large spherical structures (such as that shown here) investigated.
Tuning electronic properties and morphologies : We report a unique design platform of n‐type organic semiconductors based on asymmetrically substituted bisphenazines that enable tuning of both electronic properties and morphologies of 1D nanostructures (see figure) by using small substituents with various sizes and electronic demands.
Molecular Lego : Polyketides represent a highly diverse group of natural products with structurally intriguing carbon skeletons (see picture) which are assembled from simple acyl building blocks. A combination of chemical, biochemical, and genetics studies have provided exciting new insights into the programming of polyketide assembly and the sophisticated enzymatic machineries involved. This review highlights recent developments in the field.
Close to the edge : Photoexcitation of alizarin coupled to the surface of mesoporous TiO2 films leads to ultrafast electron transfer to the TiO2 conduction band (see picture). Complex kinetics after photoexcitation depend on the excitation energy, and indicate a position of the alizarin excited state close to the TiO2 conduction band edge, where the density of acceptor states is reduced.
The new approach of kinetically controlled ozone removal suppresses particle formation in laboratory ozonolysis experiments for methylcyclohexene and methylenecyclohexane (MCHa) at excess alkene concentrations (see graph). The results support the hypothesis that peroxy radicals are involved in organic nucleation and particle‐growth mechanisms.
In‐source oxidation : In‐source photocatalytic redox reactions for inducing peptide fragmentation are achieved on a TiO2‐derived target plate during laser desorption ionization mass spectrometry in the presence of samples and glucose acting as both an electron donor and a hole conductor (see scheme).
Visible improvements : Owing to the plasmon resonance of silver nanoparticles deposited on the surface of AgBr, the newly‐prepared plasmonic photocatalyst Ag§AgBr has a strong absorption in the visible region (see picture) and shows high efficiency in the photodegradation of organic pollutants under visible light.
