The concept of sensing metal cations by using fluorescence changes in non-aggregating AzaPc molecules that exhibit significant intramolecular charge transfer (ICT) in the OFF state was demonstrated by binding Na+ and K+ to an azacrown-5 recognition moiety. It is important to note that this concept works not only in organic solvents, but also in water after the sensor molecules are incorporated into silica nanoparticles. For more details see the Communication by V. Novakova, P. Zimcik et al. on page 5025 ff.
Asymmetric hydroamination allows the direct and selective formation of a new CN bond as a simple procedure towards valuable scalemic synthons. Recently, huge efforts have been made to overcome the challenges associated with this transformation. In their Concept article on page 4972 ff., E. Schulz and J. Hannedouche highlight the most recent and original advances in the field of asymmetric hydroamination of carbon–carbon double bonds, offering nearby developments, and addressing the next challenges.
Visible-Light Water Splitting
Water splitting by visible light has been described as one of the “holy grails” of chemistry. In their Communication on page 4986 ff., K. Maeda, K. Domen et al. demonstrated direct splitting of pure water into H2 and O2 under visible light (λ>400 nm) by using a modified TaON photocatalyst with d0 electronic configuration. Applying a less-defective TaON (here ZrO2-modified TaON), further decollated with RuOx/Cr2O3 (core/shell) nanoparticles and colloidal IrO2 as promoters, is the key to achieving the reaction.
Peptide Nucleic Acids
Selective discrimination of a single-nucleotide difference in single-stranded DNA or RNA remains a challenge with conventional DNA or RNA probes. A peptide nucleic acid (PNA)-derived probe, in which PNA forms a pseudocomplementary heteroduplex with inosine-containing DNA or RNA, effectively discriminates a single-nucleotide difference in a closely related group of sequences of single-stranded DNA and/or RNA. For more details, see the Full Paper by T. Morii et al. on page 5034 ff.