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1. Recent Advances in Dual Triplet Ketone/Transition-Metal Catalysis

   https://doi.org/10.1055/s-0042-1751444  

   Iziumchenko, Valeriia; Gevorgyan, Vladimir (July 2023, Synlett)

   Abstract Dual light-excited ketone/transition-metal catalysis is a rapidly developing field of photochemistry. It allows for versatile functionalizations of C–H or C–X bonds enabled by triplet ketone acting as a hydrogen-atom-abstracting agent, a single-electron acceptor, or a photosensitizer. This review summarizes recent developments of synthetically useful transformations promoted by the synergy between triplet ketone and transition-metal catalysis. 1 Introduction 2 Triplet Ketone Catalysis via Hydrogen Atom Transfer 2.1 Triplet Ketones with Nickel Catalysis 2.2 Triplet Ketones with Copper Catalysis 2.3 Triplet Ketones with Other Transition-Metal Catalysis 3 Triplet Ketone Catalysis via Single-Electron Transfer 4 Triplet Ketone Catalysis via Energy Transfer 5 Conclusions 

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2. Averages Along the Primes: Improving and Sparse Bounds

   https://doi.org/10.1515/conop-2020-0003  

   Han, Rui; Krause, Ben; Lacey, Michael T.; Yang, Fan (February 2020, Concrete Operators)

   Abstract Consider averages along the prime integers ℙ given by {\mathcal{A}_N}f(x) = {N^{ - 1}}\sum\limits_{p \in \mathbb{P}:p \le N} {(\log p)f(x - p).} These averages satisfy a uniform scale-free ℓ p -improving estimate. For all 1 < p < 2, there is a constant C p so that for all integer N and functions f supported on [0, N ], there holds {N^{ - 1/p'}}{\left\| {{\mathcal{A}_N}f} \right\|_{\ell p'}} \le {C_p}{N^{ - 1/p}}{\left\| f \right\|_{\ell p}}. The maximal function 𝒜 * f = sup N |𝒜 N f | satisfies ( p , p ) sparse bounds for all 1 < p < 2. The latter are the natural variants of the scale-free bounds. As a corollary, 𝒜 * is bounded on ℓ p ( w ), for all weights w in the Muckenhoupt 𝒜 p class. No prior weighted inequalities for 𝒜 * were known. 

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3. A carbene-stabilized diphosphorus: a triple-bonded diphosphorus (PP) and a bis(phosphinidene) (P–P) transfer agent

   https://doi.org/10.1039/D4SC05091F  

   Yoon, Joseph S; Abdellaoui, Mehdi; Gembicky, Milan; Bertrand, Guy (October 2024, Chemical Science)

   The bis-monosubstituted aminocarbene-P₂adduct is a generator of P₂, under the classical triple-bonded form (PP), but it also acts as a bis(phosphinidene) (P–P) synthetic equivalent. 

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4. Bacterial Community Structure Modulates Soil Phosphorus Turnover at Early Stages of Primary Succession

   https://doi.org/10.1029/2024GB008174  

   Wang, Yuhan; Bing, Haijian; Moorhead, Daryl L; Hou, Enqing; Wu, Yanhong; Wang, Jipeng; Duan, Chengjiao; Cui, Qingliang; Zhang, Zhiqin; Zhu, He; et al (October 2024, Global Biogeochemical Cycles)

   Abstract Microbes are the drivers of soil phosphorus (P) cycling in terrestrial ecosystems; however, the role of soil microbes in mediating P cycling in P‐rich soils during primary succession remains uncertain. This study examined the impacts of bacterial community structure (diversity and composition) and its functional potential (absolute abundances of P‐cycling functional genes) on soil P cycling along a 130‐year glacial chronosequence on the eastern Tibetan Plateau. Bacterial community structure was a better predictor of soil P fractions than P‐cycling genes along the chronosequence. After glacier retreat, the solubilization of inorganic P and the mineralization of organic P were significantly enhanced by increased bacterial diversity, changed interspecific interactions, and abundant species involved in soil P mineralization, thereby increasing P availability. Although 84% of P‐cycling genes were associated with organic P mineralization, these genes were more closely associated with soil organic carbon than with organic P. Bacterial carbon demand probably determined soil P turnover, indicating the dominant role of organic matter decomposition processes in P‐rich alpine soils. Moreover, the significant decrease in the complexity of the bacterial co‐occurrence network and the taxa‐gene‐P network at the later stage indicates a declining dominance of the bacterial community in driving soil P cycling with succession. Our results reveal that bacteria with a complex community structure have a prominent potential for biogeochemical P cycling in P‐rich soils during the early stages of primary succession. 

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5. Ni- and Pd-Catalyzed Enantioselective 1,2-Dicarbofunctionalization of Alkenes

   https://doi.org/10.1055/a-2108-9549  

   Kang, Taeho; Apolinar, Omar; Engle, Keary M (December 2023, Synthesis)

   Abstract Catalytic enantioselective 1,2-dicarbofunctionalization (1,2-DCF) of alkenes is a powerful transformation of growing importance in organic synthesis for constructing chiral building blocks, bioactive molecules, and agrochemicals. Both in a two- and three-component context, this family of reactions generates densely functionalized, structurally complex products in a single step. Across several distinct mechanistic pathways at play in these transformations with nickel or palladium catalysts, stereocontrol can be obtained through tailored chiral ligands. In this Review we discuss the various strategies, mechanisms, and catalysts that have been applied to achieve enantioinduction in alkene 1,2-DCF. 1 Introduction 2 Two-Component Enantioselective 1,2-DCF via Migratory Insertion 3 Two-Component Enantioselective 1,2-DCF via Radical Capture 4 Three-Component Enantioselective 1,2-DCF via Radical Capture 5 Three-Component Enantioselective 1,2-DCF via Migratory Insertion 6 Miscellaneous Mechanisms 7 Conclusion 

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