Direct Stannylation and Silylation of Arylmethanols by Palladium Catalysis.

A direct transformation of non-preactivated benzyl alcohols to benzyl stannanes and benzyl silanes was realized through Pd-catalyzed C(sp3)-O activation process. By using versatile tin and silicon sources, these reactions exhibit a broad substrate scope and a high efficiency under mild conditions, affording functionalized benzyl and allylic stannanes and benzylsilanes with high yields. The successful implementation of gram-scale stannylation/silylation as well as the one-pot Stille coupling reaction demonstrates the potential application of this method in organic synthesis. Both experimental and theoretical investigations reveal the mechanistic details of this reaction.

A Library of Rare Earth Oxide Ultrathin Nanowires with Polymer-Like Behaviors.

Ultrathin nanowires (NWs) have always attracted the attention of researchers due to their unique properties, but their facile synthesis is still a great challenge. Herein we developed a general method for the synthesis of rare earth (RE) oxide ultrathin NWs at atmospheric pressure and low temperature (50 °C). The formation mechanism of ultrathin NWs lies in two aspects: thermodynamic advantage of one dimensional (1D) growth at low temperature, and supplement of effective monomers. As an extension, fifteen kinds of RE oxide ultrathin NWs were synthesized through this strategy, and they all exhibited polymer-like behaviors. Meanwhile, the high viscosity, organic gel, wet- and electro-spinning of Ce-Mo-O NWs were studied in detail, demonstrating the similarity of ultrathin inorganic NWs to polymers. In addition, the Ce-Mo-O ultrathin NWs were used as photocatalysts for toluene oxidation and showed excellent performance with toluene conversion ratio of 83.8 %, suggesting their potential application in organic photocatalysis.

Transition Metal Free Stannylation of Alkyl Halides: The Rapid Synthesis of Alkyltrimethylstannanes.

A transition metal free stannylation reaction of alkyl bromides and iodides with hexamethyldistannane has been developed. This protocol is operationally convenient and features a rapid reaction and good functional group tolerance. A wide range of functionalized primary and secondary alkyl and benzyl trimethyl stannanes are prepared in moderate to excellent yields. The success of the gram-scale procedure and tandem Stille coupling reaction has allowed this protocol to demonstrate potential for application in organic synthesis. Both experimental and theoretical studies reveal the mechanistic details of this stannylation reaction.

Visible-Light-Driven Synthesis of Arylstannanes from Arylazo Sulfones.

The visible-light-driven preparation of (hetero)aryl stannanes was carried out under both photocatalyst- and metal-free conditions via irradiation of arylazo sulfones in the presence of hexaalkyldistannanes. The reaction shows a high efficiency and a wide substrates scope. The resulting crude organotin derivatives can be directly employed in a Stille protocol.

Synthesis of N-arylsulfonamides through a Pd-catalyzed reduction coupling reaction of nitroarenes with sodium arylsulfinates.

A novel one-step direct reductive coupling reaction between nitroarenes and sodium arylsulfinates was realized in the presence of an inexpensive Pd/C catalyst. In this procedure, readily available nitroarenes are employed as the nitrogen sources, and sodium arylsulfinates serve as both coupling partners and reductants. The method features high efficiency by using cheap Pd/C with low catalyst loading and good functional group tolerance in the absence of any additional reductants or ligands. This facile and mild synthetic method enables the high efficiency synthesis of functionalized N-arylsulfonamides from readily available substrates.