Graphitic carbon nitride (g‐CN) is a transition metal free semiconductor that mediates a variety of photocatalytic reactions. Although photoinduced electron transfer is often postulated in the mechanism, proton‐coupled electron transfer (PCET) is a more favorable pathway for substrates possessing X−H bonds. Upon excitation of an (sp2)N‐rich structure of g‐CN with visible light, it behaves as a photobase—it undergoes reductive quenching accompanied by abstraction of a proton from a substrate. The results of modeling allowed us to identify active sites for PCET—the ‘triangular pockets’ on the edge facets of g‐CN. We employ excited state PCET from the substrate to g‐CN to selectively cleavethe endo‐(sp3)C−H bond in oxazolidine‐2‐ones followed by trapping the radical with O2. This reaction affords 1,3‐oxazolidine‐2,4‐diones. Measurement of the apparent pKa value and modeling suggest that g‐CN excited state can cleave X−H bonds that are characterized by bond dissociation free energy (BDFE) ≈100 kcal mol−1.

Synthesis, isomerism, and fungicidal activity against potato diseases of new (5 Z)-[2-(2,4,5-trioxopyrrolidin-3-ylidene)-4-oxo-1,3-thiazolidin-5-ylidene]acetate derivatives with 1,3-thiazolidine-4-one and pyrrolidine-2,3,5-trione moieties linked by an exocyclic C═C bond were described. Their structures were clearly confirmed by spectroscopic and spectrometric data (Fourier transform infrared spectroscopy, H andC nuclear magnetic resonance, and mass spectrometry), elemental analysis, and X-ray diffraction crystallography. A bioassay for antifungal activity in vitro against Phytophthora infestans, Fusariun solani, Alternaria solani, Rhizoctonia solani, and Colletotrichum coccodes demonstrated that 2,4,5-trioxopyrrolidin-1,3-thiazolidine derivatives exhibited a relatively broad spectrum of antifungal activity. One of the compounds showed considerable activity against all of the strains; in the case of F. solani, P. infestans, and A. solani, it possesses comparable or better fungicidal efficacy than the positive control Consento. Consequently, this compound is a promising fungicidal candidate for plant protection.

With photovoltaics becoming a mature, commercially feasible technology, society is willing to allocate resources for developing and deploying new technologies based on using solar light. Analysis of projects supported by the European Commission in the past decade indicates exponential growth of funding to photocatalytic (PC) and photoelectrocatalytic (PEC) technologies that aim either at technology readiness levels (TRLs) TRL 1–3 or TRL > 3, with more than 75 Mio€ allocated from the year 2019 onward. This review provides a summary of PC and PEC processes for the synthesis of bulk commodities such as solvents and fuels, as well as chemicals for niche applications. An overview of photoreactors for photocatalysis on a larger scale is provided. The review rounds off with the summary of reactions performed at lab scale under natural outdoor solar light to illustrate conceptual opportunities offered by solar-driven chemistry beyond the reduction of CO 2 and water splitting. The authors offer their vision of the impact of this area of research on society and the economy.

Following our previous studies on potassium poly(heptazine imide) (K‐PHI), that is, catalyzed photooxidative [3+2] aldoxime‐to‐nitrile addition to form 1,2,4‐oxadiazoles, we discovered that electron‐rich oximes yield the parent aldehydes instead of target products. In this work, the mechanism of this singlet oxygen‐mediated deoximation process was established using a series of control reactions and spectroscopic measurements such as steady‐state and time‐resolved fluorescence quenching experiments. Additionally, the singlet‐triplet energy gap value was obtained for K‐PHI in suspension, and the reaction scope was broadened to include ketoximes.

Graphitisches Kohlenstoffnitrid (g-CN) ist ein übergangsmetallfreier Halbleiter, der eine Vielzahl von photokatalytischen Reaktionen unterstützt. Obwohl oft ein photoinduzierter Elektronentransfer als Mechanismus postuliert wird, ist der protonengekoppelte Elektronentransfer (PCET) der bevorzugte Weg für Substrate mit XÀ H-Bindungen. Bei der Anregung einer (sp 2 )N-reichen Struktur von g-CN mit sichtbarem Licht verhält sie sich wie eine Photobase -es kommt zu einem reduktivem Quenching, begleitet von der Abstraktion eines Protons aus einem Substrat. Die Ergebnisse der Modellierung ermöglichten es uns, aktive Stellen für PCET zu identifizieren -die "dreieckigen Taschen" an den Kantenfacetten von g-CN. Excited-State-PCET vom Substrat zu g-CN wurde eingesetzt um die endo-(sp 3 )CÀ H-Bindung in Oxazolidin-2-onen selektiv zu spalten, gefolgt vom Einfangen des Radikals mit O 2 . Diese Reaktion ergibt 1,3-Oxazolidin-2,4-Dionen. Die Messung des scheinbaren pK a -Wertes und die Modellierung deuten darauf hin, dass der angeregte g-CN-Zustand XÀ H-Bindungen spalten kann, die durch eine freie Bindungsdissoziationsenergie (BDFE) von � 100 kcal mol À 1 gekennzeichnet sind.[ + ] Diese Autoren haben zu gleichen Teilen zu der Arbeit beigetragen.