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1. Intramolecular Charge Transfer in Antiaromatic Donor/Acceptor‐Fused s ‐Indacenes

   https://doi.org/10.1002/anie.202420989  

   Demachkie, Isabella S; Miller, Michael P; Warren, Gabrielle I; Barker, Joshua E; Strand, Eric T; Zakharov, Lev N; Haley, Michael M (February 2025, Angewandte Chemie International Edition)

   Abstract Herein we report the synthesis and characterization of four donor/acceptor‐fuseds‐indacenes via the late‐stage oxidation of a family of unsymmetrical benzofuran/benzothiophene‐s‐indacene regioisomers. A thorough study of their properties through experimental and computational analysis has revealed the effect of asymmetry on the molecular properties associated with antiaromaticity, as well as a strong correlation between antiaromaticity and intramolecular charge transfer (ICT). The strength of the charge transfer depends on the fusion orientation of the donor and acceptor motifs relative to thes‐indacene core. The two most antiaromatic oxidized isomers exhibit strong evidence of ICT with 30 and 40 nm solvatochromic shifts. 

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2. Voluntary environmental effort under ( s , S ) inventory policy*

   https://doi.org/10.1080/00207543.2023.2242968  

   Bensoussan, Alain; El_Ouardighi, Fouad (January 2024, International Journal of Production Research)

   Prior research on inventory control has been wide ranging, yet the environmental implications of an (s,S) inventory policy remain uninvestigated. This paper seeks to bridge the gap by characterising a firm’s voluntary environmental policy in the setup of an (s,S) inventory control policy. We suggest a mixed model structure wherein, due to the presence of fixed production costs, the inventory is determined continuously by sales and impulsively with ordering decisions obeying an optimal stopping process, while the uncertain sales process is controlled by continuous-time environmental goodwill-related decisions. We show that a firm should successively use voluntary environmental efforts to stimulate its sales when there is inventory and to increase backlogging to improve its production efficiency. Given the recurrent pattern of this policy, we conclude that voluntary environmental efforts under an (s,S) inventory control is not compatible with using these efforts as a means to generate ephemeral reputation insurance. 

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3. Asymmetric [3+ n ]‐Cycloaddition Reactions of Donor‐Acceptor Cyclopropanes

   https://doi.org/10.1002/cctc.202301090  

   Bao, Ming; Doyle, Michael P (December 2023, ChemCatChem)

   Abstract [3+n]‐Cycloaddition reactions that employ donor‐acceptor cyclopropanes using either chiral catalysts and racemic cyclopropanes or achiral catalysts and chiral, non‐racemic, cyclopropanes have become useful transformations for the construction of carbocyclic and heterocyclic compounds, with both processes offering mechanistic and structural advantages in ring formation. Although the vast majority of asymmetric cycloaddition reactions of donor‐acceptor cyclopropanes have been performed with racemic cyclopropane compounds catalyzed by Lewis acids with chiral ligands, optically active cyclopropane compounds can serve the same role using Lewis acids without chiral ligands. This review covers the use of chiral catalysts with racemic donor‐acceptor cyclopropanes and the use of chiral non‐racemic donor‐acceptor cyclopropanes with achiral Lewis acid catalysts. 

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4. Strong acceptor incorporated phenothiazine-C ₆₀ multi-redox push–pull conjugates: demonstration of C ₆₀ 's superior electron acceptor characteristics

   https://doi.org/10.1039/D5SC02950C  

   Gupta, Pankaj K; Ileperuma, Chamari V; Misra, Rajneesh; D'Souza, Francis (July 2025, Chemical Science)

   Cooper, A (Ed.)

   Novel bis-phenothiazine-C₆₀conjugates, incorporating strong electron acceptors, TCBD or DCNQ, between the two phenothiazine entities, have been newly synthesized. The involvement of C₆₀as the terminal electron acceptor is demonstrated. 

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5. The s Process and Beyond

   https://doi.org/10.1146/annurev-nucl-102422-080857  

   Lugaro, Maria; Pignatari, Marco; Reifarth, René; Wiescher, Michael (September 2023, Annual Review of Nuclear and Particle Science)

   Neutron captures produce the vast majority of abundances of elements heavier than iron in the Universe. Beyond the classical slow ( s) and rapid ( r) processes, there is observational evidence for neutron-capture processes that operate at neutron densities in between, at different distances from the valley of β stability. Here, we review the main properties of the s process within the general context of neutron-capture processes and the nuclear physics input required to investigate it. We describe massive stars and asymptotic giant branch stars as the s-process astrophysical sites and discuss the related physical uncertainties. We also present current observational evidence for the s process and beyond, which ranges from stellar spectroscopic observations to laboratory analysis of meteorites. 

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