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The first occurrence of Leucoinocybe in the Chinese mycobiota is reported, and Leucoinocybe lishuiensis, a new species from the Baishanzu National Forest Park, Lishui City, Zhejiang Province, is described. The new species is characterized by the presence of a brown pileus, white lamellae, narrowly ellipsoid basidiospores, prominently thick-walled pileocystidia and caulocystidia and growth on living wood in Picea, Pinus, Populus, and Quercus mixed forests. A comprehensive morphological description, photographs, line drawings, and comparisons of related species are provided. Molecular analyses of a combined dataset of nuclear rDNA internal transcribed spacer (ITS) and large ribosomal subunit (LSU) sequences using maximum likelihood and Bayesian inference methods were conducted to elucidate the taxonomic status of L. lishuiensis. The phylogenetic analyses coupled with morphological observations confirmed our recognition of this new species.

Catalytic transformation of alcohols via metal-catalyzed cross-coupling reactions is very important, but it typically relies on a multistep procedure. We here report a dynamic kinetic cross-coupling approach for the direct functionalization of alcohols. The feasibility of this strategy is demonstrated by a nickel-catalyzed cross-electrophile arylation reaction of benzyl alcohols with (hetero)aryl electrophiles. The reaction proceeds with a broad substrate scope of both coupling partners. The electron-rich, electron-poor, and ortho-/meta-/para-substituted (hetero)aryl electrophiles (e.g., Ar–OTf, Ar–I, Ar–Br, and inert Ar–Cl) all coupled well. Most of the functionalities, including aldehyde, ketone, amide, ester, nitrile, sulfone, furan, thiophene, benzothiophene, pyridine, quinolone, Ar–SiMe3, Ar–Bpin, and Ar–SnBu3, were tolerated. The dynamic nature of this method enables the direct arylation of benzylic alcohol in the presence of various nucleophilic groups, including nonactivated primary/secondary/tertiary alcohols, phenols, and free indoles. It thus offers a robust alternative to existing methods for the precise construction of diarylmethanes. The synthetic utility of the method was demonstrated by a concise synthesis of biologically active molecules and by its application to peptide modification and conjugation. Preliminary mechanistic studies revealed that the reaction of in situ formed benzyl oxalates with nickel, possibly via a radical process, is an initial step in the reaction with aryl electrophiles.

Enantioselective cross-electrophile reactions remain a challenging subject in metal catalysis, and with respect to data, studies have mainly focused on stereoconvergent reactions of racemic alkyl electrophiles. Here, we report an enantioselective cross-electrophile aryl-alkenylation reaction of unactivated alkenes. This method provides access to a number of biologically important chiral molecules such as dihydrobenzofurans, indolines, and indanes. The incorporated alkenyl group is suitable for further reactions that can lead to an increase in molecular diversity and complexity. The reaction proceeds under mild conditions at room temperature, and an easily accessible chiral pyrox ligand is used to afford products with high enantioselectivity. The synthetic utility of this method is demonstrated by enabling the modification of complex molecules such as peptides, indometacin, and steroids.

Transition-metal-catalyzed sila-cycloaddition has been a promising tool for accessing silacarbocycle derivatives, but the approach has been limited to a selection of well-defined sila-synthons. Herein, we demonstrate the potential of chlorosilanes, which are industrial feedstock chemicals, for this type of reaction under reductive nickel catalysis. This work extends the scope of reductive coupling from carbocycle to silacarbocycle synthesis and from single C–Si bond formation to sila-cycloaddition reactions. The reaction proceeds under mild conditions and shows good substrate scope and functionality tolerance, and it offers new access to silacyclopent-3-enes and spiro silacarbocycles. The optical properties of several spiro dithienosiloles as well as structural variations of the products are demonstrated.

The construction of secondary alkylsilanes is a challenging subject in the synthetic community. The cross-coupling provides a practical solution to address this problem, but it typically relies on organometallic species. Herein, we report an Mn-mediated reductive C(sp3)–Si coupling to synthesize these compounds from alkyl and silyl electrophiles. This approach avoids the requirement for activation of Si–Cl by transition metals and thus allows for the coupling of various common chlorosilanes. The reaction proceeds under mild conditions and shows good functional group compatibility. The method offers access to α-silylated organophosphorus and sulfones with a scope that is complementary to those obtained from the established methods.

Cross-electrophile C–Si coupling has emerged as a promising tool for the construction of organosilanes, but the potential of this method remains largely unexplored. Herein, we report a C(sp3)–Si coupling of unactivated alkyl bromides with vinyl chlorosilanes. The reaction proceeds under mild conditions, and it offers a new approach to alkylsilanes. Functionalities such as Grignard-sensitive groups (e.g., acid, amide, alcohol, ketone, and ester), acid-sensitive groups (e.g., ketal and THP protection), alkyl fluoride and chloride, aryl bromide, alkyl tosylate and mesylate, silyl ether, and amine were tolerated. Incorporation of the −Si(vinyl)R2moiety into complex molecules and the immobilization of a glass surface by formed organosilanes were demonstrated.

The regiocontrolled functionalization of 1,3-dienes has become a powerful tool for divergent synthesis, yet it remains a long-standing challenge for aliphatic substrates. Herein, we report a reductive approach for a branch-selective 1,2-hydrovinylation of aliphatic 1,3-dienes with R–X electrophiles, which represents a new selectivity pattern for diene functionalization. Simple butadiene, aromatic 1,3-dienes, and highly conjugated polyene were also tolerated. The combination of Ni(0) and the phosphine–nitrile ligand generally resulted in >20:1 regioselectivity with the retention of the geometry of the C3–C4double bonds. This reaction proceeds with a broad substrate scope, and it allows for the conjugation of two biologically active units to form more complex polyene molecules, such as tetraene and pentaene as well as heptaene.