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1. Sensitized Photooxidation of Ortho ‐Prenyl Phenol: Biomimetic Dihydrobenzofuran Synthesis and Total ¹O₂ Quenching ^†

   https://doi.org/10.1111/php.13689  

   Jabeen, Shakeela; Ghosh, Goutam; Lapoot, Lloyd; Durantini, Andrés M.; Greer, Alexander (September 2022, Photochemistry and Photobiology)

   Abstract The sensitized photooxidation ofortho‐prenyl phenol is described with evidence that solvent aproticity favors the formation of a dihydrobenzofuran [2‐(prop‐1‐en‐2‐yl)‐2,3‐dihydrobenzofuran], a moiety commonly found in natural products. Benzene solvent increased the total quenching rate constant (k_T) of singlet oxygen with prenyl phenol by ~10‐fold compared to methanol. A mechanism is proposed with preferential addition of singlet oxygen to prenyl site due to hydrogen bonding with the phenol OH group, which causes a divergence away from the singlet oxygen ‘ene’ reaction toward the dihydrobenzofuran as the major product. The reaction is a mixed photooxidized system since an epoxide arises by a type I sensitized photooxidation. 

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2. A chemical dynamics study on the gas phase formation of thioformaldehyde (H ₂ CS) and its thiohydroxycarbene isomer (HCSH)

   https://doi.org/10.1073/pnas.2004881117  

   Doddipatla, Srinivas; He, Chao; Kaiser, Ralf I.; Luo, Yuheng; Sun, Rui; Galimova, Galiya R.; Mebel, Alexander M.; Millar, Tom J. (September 2020, Proceedings of the National Academy of Sciences)

   null (Ed.)

   Complex organosulfur molecules are ubiquitous in interstellar molecular clouds, but their fundamental formation mechanisms have remained largely elusive. These processes are of critical importance in initiating a series of elementary chemical reactions, leading eventually to organosulfur molecules—among them potential precursors to iron-sulfide grains and to astrobiologically important molecules, such as the amino acid cysteine. Here, we reveal through laboratory experiments, electronic-structure theory, quasi-classical trajectory studies, and astrochemical modeling that the organosulfur chemistry can be initiated in star-forming regions via the elementary gas-phase reaction of methylidyne radicals with hydrogen sulfide, leading to thioformaldehyde (H 2 CS) and its thiohydroxycarbene isomer (HCSH). The facile route to two of the simplest organosulfur molecules via a single-collision event affords persuasive evidence for a likely source of organosulfur molecules in star-forming regions. These fundamental reaction mechanisms are valuable to facilitate an understanding of the origin and evolution of the molecular universe and, in particular, of sulfur in our Galaxy. 

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3. Solution Studies of a Water-Stable, Trivalent Antimony Pnictogen Bonding Anion Receptor with High Binding Affinities for CN ^– , OCN ^– , and OAc ^–

   https://doi.org/10.1021/acs.inorgchem.3c01887  

   Qiu, Jinchun; Bateman, Curt N.; Lu, Shuai; George, Gary C.; Li, Xiaopeng; Gorden, John D.; Vasylevskyi, Serhii; Cozzolino, Anthony F. (August 2023, Inorganic Chemistry)

   The solution phase anion binding behavior of a water-stable bidentate pnictogen bond donor was studied. A modest change in the visible absorption spectrum allowed for the determination of the binding constants. High binding constants were observed with cyanide, cyanate, and acetate, and these were corroborated with density functional theory (DFT) calculations. The receptor could be recovered free from the anion following treatment with methyl triflate, confirming that it remains intact. The tight binding of cyanide and water stability were exploited to use this system as a supramolecular catalyst in a phase-transfer Strecker reaction, further demonstrating the utility of pnictogen bonding as a tool in noncovalent catalysis. 

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4. Green synthesis of CdS/Ni _x S _y nanoparticles as a route towards sustainable and scalable photocatalysts

   https://doi.org/10.1039/D2GC03361E  

   Sakizadeh, John; Cline, Joseph P.; Wolfe, Eva; Thorpe, Ryan; Snyder, Mark A.; Kiely, Christopher J.; McIntosh, Steven (October 2022, Green Chemistry)

   If hydrogen evolution photocatalysis are to be deployed at industrial scale, the synthesis of these photocatalytic materials must be both economically and environmentally scalable. This suggests that we must move towards green synthesis of earth-abundant photocatalysts while also maintaining high catalytic performance. Herein, we present the enzymatically driven, aqueous phase, low temperature, synthesis of an earth-abundant nickel sulfide (Ni x S y ) hydrogen evolution cocatalyst, and its integration into a CdS/Ni x S y heterostructured photocatalyst. This resulting photocatalyst provides hydrogen evolution rates (10 500 μmol h −1 g −1 ) comparable to photocatalysts prepared by more traditional routes. Furthermore, the Ni x S y is demonstrated to provide similar activity enhancement to the more traditional, but also more expensive platinum cocatalysts. To achieve this result, we carefully studied and engineered the synthesis environment to maintain enzyme activity towards HS − production while sustaining a sufficient concentration of free Ni 2+ in solution to enable reaction and formation of Ni x S y . Ultimately, this work provides a methodology to control the coordination of metal precursors in low temperature, aqueous systems to allow for precipitation of catalytically active materials and demonstrates the viability of green synthesis pathways for photocatalysts. 

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5. Multicomponent supramolecular hydrogels composed of cationic phenylalanine derivatives and anionic amino acids

   https://doi.org/10.1039/D4FD00198B  

   Ghosh, Shruti; Distaffen, Hannah E; Jones, Christopher W; Nilsson, Bradley L (January 2025, Faraday Discussions)

   The properties of supramolecular hydrogels of cationic phenylalanine derivatives are modified by multicomponent formulation with anionic amino acids. 

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