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The reaction of dibenzonorcarynyliden(e/oid) with phencyclone was recently reported to give a congested spiropentane withendostereochemistry. Herein we report that, in sharp contrast, an analogous reaction using tetracyclone, instead of phencyclone, gives the highly crowded title spiropentane but withexostereochemistry as determined by X-ray crystallography. This new tetracyclone adduct (C₄₄H₃₀O) crystallizes upon slow evaporation from hexanes/ethyl acetate in the monoclinic crystal system andP2₁/n(No. 14) space group. It has one molecule in the asymmetric unit and four molecules per unit cell. DLPNO-CCSD(T)/def2-TZVP//B3LYP/def2-SVP calculations indicate that theendospiropentane diastereomers from phencyclone and tetracyclone are both more stable than the correspondingexoforms by 6.68 and 5.35 kcal mol⁻¹, respectively. As noted previously in the phencyclone system, favorable π-stacking interactions between the two flat biphenyl moieties in the product and transition state may lead to the preferential formation of theendodiastereomer. However, the ability of the phenyl rings in the 3,4-position of the tetracyclone component to rotate could introduce destabilizing steric interactions in the transition state that hinder formation of theendodiastereomer in favor of the less thermodynamically stableexoisomer. 

The generation of saturated carbenes (A) and unsaturated carbenes (B) from cyclopropanated aromatic systems is reviewed. 

Copper oxide nanostructures are widely used for various applications due to their unique optical and electrical properties. In this work, we demonstrate an atmospheric laser-induced oxidation technique for the fabrication of highly electrochemically active copper oxide hierarchical micro/nano structures on copper surfaces to achieve highly sensitive non-enzymatic glucose sensing performance. The effect of laser processing power on the composition, crystallinity, microstructure, wettability, and color of the laser-induced oxide on copper (LIO-Cu) surface was systematically studied using scanning electron microscopy (SEM), grazing incidence X-ray diffraction (GI-XRD), Raman spectroscopy, energy dispersive X-ray spectroscopy (EDX), EDX-mapping, water contact angle measurements, and optical microscopy. Results of these investigations showed a remarkable increase in copper oxide composition by increasing the laser processing power. The pore size distribution and surface area of the pristine and LIO-Cu sample estimated by N 2 adsorption–desorption data showed a developed mesoporous LIO-Cu structure. The size of the generated nano-oxides, crystallinity, and electroactivity of the LIO-Cu were observed to be adjustable by the laser processing power. The electrocatalytic activity of LIO-Cu surfaces was studied by means of cyclic voltammetry (CV) within a potential window of −0.8 to +0.8 V and chronoamperometry in an applied optimized potential of +0.6 V, in 0.1 M NaOH solution and phosphate buffer solution (PBS), respectively. LIO-Cu surfaces with optimized laser processing powers exhibited a sensitivity of 6950 μA mM −1 cm −2 within a wide linear range from 0.01 to 5 mM, with exceptional specificity and response time (<3 seconds). The sensors also showed excellent response stability over a course of 50 days that was originated from the binder-free robust electroactive film fabricated directly onto the copper surface. The demonstrated one-step LIO processing onto commercial metal films, can potentially be applied for tuneable and scalable roll-to-roll fabrication of a wide range of high surface area metal oxide micro/nano structures for non-enzymatic biosensing and electrochemical applications. 

Abstract Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.