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An efficient method for the synthesis of heterogeneous gold catalysts has been developed. These catalysts were easily assembled from readily available silica materials and gold complexes. The heterogeneous catalysts exhibited superior reactivity in various reactions where protodeauration is the rate-limiting step. Dramatic enhancement in regio- and enantioselectivity was observed when compared to the homogeneous unsupported gold catalyst. The catalysts are easily recovered and recycled up to 11 times without loss of enantioselectivity.

A combination of visible light photocatalysis and gold catalysis is applied to a ring expansion-oxidative arylation reaction. The reaction provides an entry into functionalized cyclic ketones from the coupling reaction of alkenyl and allenyl cycloalkanols with aryl diazonium salts. A mechanism involving generation of an electrophilic gold(III)-aryl intermediate is proposed on the basis of mechanistic studies, including time-resolved FT-IR spectroscopy.

Chlorosilanes are the most accessible feedstock chemical in the organosilicon world. Cross-coupling involving chlorosilanes by transition metal catalysis offers a promising way for the production of organosilanes, which play essential roles in many important research areas, including agriculture, medicinal chemistry, and material science. This chemistry is firstly realized by coupling chlorosilanes with organometallic species and then extended to the silyl-Heck reaction with alkenes. Very recently, the cross-electrophile coupling of chlorosilanes has also been established. In this review, we summarize the progress of this chemistry. 1 Introduction 2 Cross-Coupling of Chlorosilanes with Organometallic Reagents 3 The Silyl-Heck Reaction of Chlorosilanes and Alkenes 4 Reductive Cross-Coupling of Chlorosilanes with Electrophiles 5 Summary and Outlook [ABSTRACT FROM AUTHOR]

Catalytic, three‐component, cross‐electrophile reactions have recently emerged as a promising tool for molecular diversification, but studies have focused mainly on the alkyl‐carbonations of alkenes. Herein, the scope of this method has been extended to conjugated dienes and silicon chemistry through silylative difunctionalization of 1,3‐dienes with chlorosilanes and aryl bromides. The reaction proceeds under mild conditions to afford 1,2‐linear‐silylated products, a selectivity that is different to those obtained from conventional methods via an intermediary of H(C)‐η3‐π‐allylmetal species. Preliminary mechanistic studies reveal that chlorosilane reacts with 1,3‐diene first and then couples with aryl bromide. [ABSTRACT FROM AUTHOR]

We report here a new method for the synthesis of organohydrosilanes from phenols and ketones. This method is established through reductive C−Si coupling of chlorohydrosilanes via unconventional Si−Cl cleavage. The reaction offers access to aryl‐ and alkenylhydrosilanes with a scope that is complementary to those of the established methods. Electron‐rich, electron‐poor, and ortho‐/meta‐/para‐substituted (hetero)aryl electrophiles, as well as cyclic and acyclic alkenyl electrophiles, were coupled successfully. Functionalities, including Grignard‐sensitive groups (e.g. primary amine, amide, phenol, ketone, ester, and free indole), acid‐sensitive groups (e.g. ketal and THP protection), alkyl‐Cl, pyridine, furan, thiophene, Ar‐Bpin, and Ar‐SiMe3, were tolerated. Gram‐scale reaction, incorporation of ‐Si(H)R2 into complex biologically active molecules, and derivatization of formed organohydrosilanes are demonstrated. [ABSTRACT FROM AUTHOR]

Catalytic alkylation of stable alkenyl C−O electrophiles is synthetically appealing, but studies to date have typically focused on the reactions with alkyl Grignard reagents. We report herein a cross‐electrophile reaction of alkenyl acetates with alkyl bromides. This work has enabled a new method for the synthesis of aliphatic alkenes from alkenyl acetates to be established that can be used to add more structural complexity and molecular diversity with enhanced functionality tolerance. The method allows for a gram‐scale reaction and modification of biologically active molecules, and it affords access to useful building blocks. Preliminary mechanistic studies reveal that the NiI species plays an essential role for the success of the coupling of these two reactivity‐mismatched electrophiles. [ABSTRACT FROM AUTHOR]