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As global biodiversity hotspots, wild fruit forests play key ecological functions, providing essential ecosystem services such as carbon storage, soil retention, and water conservation, and support food chains and biodiversity conservation through key species. Climate change, with rising temperatures and altered precipitation patterns, threatens wild fruit forests by reducing the habitats and numbers of key species, potentially turning these ecosystems from carbon sinks to sources and diminishing overall biodiversity and ecosystem services. However, research on how these changes affect important species' habitats and carbon dynamics remains insufficient. To address this, we analysed habitat suitability for three important species (Prunus armeniaca L., Malus sieversii, and Prunus ledebouriana (Schltdl.) Y.Y.Yao with the aim of informing conservation strategies. We used biomod2 to integrate environmental and species data using six methods, encompassing 12 models. We predicted overlapping geographical distributions of three species, analysing their ecological niches and environmental interactions using global datasets to understand their adaptations. This analysis revealed ecological niche shifts and reductions in resource utilisation in both current and future scenarios. Their distribution centres will move poleward under the influence of bioclimatic factors and human activities. In conclusion, protecting P. armeniaca, M. sieversii, and P. ledebouriana is essential for the conservation and overall health of wild fruit forest ecosystems. This study provides new insights into climate change, habitat loss, informing conservation and resilience strategies. [ABSTRACT FROM AUTHOR]

Small aromatic molecules with oxygen-containing functional groups are a promising class of fuel additives, as they can be readily sourced from depolymerized lignin. These oxygenated aromatic compounds (OACs) show a lower sooting tendency than aromatic hydrocarbons, but OACs having alkyl groups such as ethylphenol show a higher sooting tendency than other OACs such as phenol and anisole, despite the oxygen moiety. In this study, we investigate the relationship between chemical structure and soot precursor formation to explain observed differences in the sooting tendency of OACs and to gain insight into how alkyl or oxygenated substituents on the aromatic ring affect soot precursor formation. The weakest bond for 15 aromatic compounds was identified and cleavage of these bonds was shown to generate either benzyl or phenoxy radicals. A linear relationship between standard enthalpy of formation (ΔH f o) of these radicals and the yield sooting index (YSI) was found, and thus ΔH f ° can be applied as a metric to estimate YSIs of various aromatic compounds; higher ΔH f o of a radical indicates an increase in the radical reactivity and leads to more soot precursor formation. Flow reactor experiments were performed for 2-ethylphenol and 3-ethylphenol to elucidate how ortho and meta substitution effects the sooting tendency. Soot precursors were identified from the experiment and their formation pathways were investigated computationally. 2-ethylphenol produces more oxygenated products than 3-ethylphenol since the ortho position has increased resonance stabilization of radical intermediates, which leads to lower YSI. These results further inform the selection of potential biomass-derived fuel blendstocks that have favorable sooting tendencies. [ABSTRACT FROM AUTHOR]

We detail the development of the first enantioselective synthetic route to euonyminol ( 1 ), the most heavily oxidized member of the dihydro-β-agarofuran sesquiterpenes and the nucleus of the macrocyclic alkaloids known as the cathedulins. Key steps in the synthetic sequence include a novel, formal oxyalkylation reaction of an allylic alcohol by [3 + 2] cycloaddition; a tandem lactonization-epoxide opening reaction to form the trans -C2-C3 vicinal diol residue; and a late-stage diastereoselective trimethylaluminum-mediated α-ketol rearrangement. We report an improved synthesis of the advanced unsaturated ketone intermediate 64 by means of a 6- endo -dig radical cyclization of the enyne 42 . This strategy nearly doubled the yield through the intermediate steps in the synthesis and avoided a problematic inversion of stereochemistry required in the first-generation approach. Computational studies suggest that the mechanism of this transformation proceeds via a direct 6- endo -trig cyclization, although a competing 5- exo -trig cyclization, followed by a rearrangement, is also energetically viable. We also detail the challenges associated with manipulating the oxidation state of late-stage intermediates, which may inform efforts to access other derivatives such as 9- epi -euonyminol or 8- epi -euonyminol. Our successful synthetic strategy provides a foundation to synthesize the more complex cathedulins.

Heterogenization of homogenous catalysts on electrode surfaces provides a valuable approach for characterization of catalytic processes in operando conditions using surface selective spectroelectrochemistry methods. Ligand design plays a central role in the attachment mode and the resulting functionality of the heterogenized catalyst as determined by the orientation of the catalyst relative to the surface and the nature of specific interactions that modulate the redox properties under the heterogeneous electrode conditions. Here, we introduce new [Re(L)(CO) 3 Cl] catalysts for CO 2 reduction with sulfur-based anchoring groups on a bipyridyl ligand, where L = 3,3'-disulfide-2,2'-bipyridine (SSbpy) and 3,3'-thio-2,2'-bipyridine (Sbpy). Spectroscopic and electrochemical analysis complemented by computational modeling at the density functional theory level identify the complex [Re(SSbpy)(CO) 3 Cl] as a multi-electron acceptor that combines the redox properties of both the rhenium tricarbonyl core and the disulfide functional group on the bipyridyl ligand. The first reduction at -0.85 V (vs. SCE) involves a two-electron process that breaks the disulfide bond, activating it for surface attachment. The heterogenized complex exhibits robust anchoring on gold surfaces, as probed by vibrational sum-frequency generation (SFG) spectroscopy. The binding configuration is normal to the surface, exposing the active site to the CO 2 substrate in solution. The attachment mode is thus particularly suitable for electrocatalytic CO 2 reduction., (Copyright © 2020 Cattaneo, Guo, Kelly, Videla, Kiefer, Gebre, Ge, Liu, Wu, Lian and Batista.)