Preparation of Alkyl Di(-tolyl)sulfonium Salts and Their Application in Metal-Free C(sp)-C(sp) and C(sp)-C(sp) Bond Formations.

Alkyldiarylsulfonium salts were synthesized by a combination of active sulfonium species, prepared through the activation of diarylsulfoxide, and alkyl nucleophiles. The isolated sulfonium salts were subjected to the allylation and cyclopropanation of the active methylene compounds and metal-free C(sp)-C(sp) couplings via oxyallyl cation intermediates under mild conditions. The series of reactions included an umpolung strategy for the coupling of alkyl nucleophiles and metal-free C-C bond formation using sulfonium salts.

Mechanisms controlling the stabilization of soil organic matter in agricultural soils as amended with contrasting organic amendments: Insights based on physical fractionation coupled with C NMR spectroscopy.

Soil organic matter (SOM) has vital roles in the global carbon (C) cycle and the use of organic amendments (OAs) to maintain or improve SOM levels is a promising practice. However, the mechanisms underlying SOM stabilization in OA-amended soils remain insufficiently resolved. For more effective understanding on such issues, we examined soil samples from a long-term experimental plot (26-31 years) that included six treatments, namely, a chemical fertilizer (CF) alone (CF), a bark compost plus CF (BC + CF), a coffee residue compost plus CF (CRC + CF), a cattle manure compost plus CF (CMC + CF), and a cattle manure (CMC) or sewage sludge compost (SSC) alone at a higher application rate, using physical fractionation.