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The asymmetric hydrophosphination of cyclopropenes with phosphines is of much interest and importance, but has remained hardly explored to date probably because of the lack of suitable catalysts. We report here the diastereo‐ and enantioselective hydrophosphination of 3,3‐disubstituted cyclopropenes with phosphines by a chiral lanthanocene catalyst bearing the C2‐symmetric 5,6‐dioxy‐4,7‐trans‐dialkyl‐substituted tetrahydroindenyl ligands. This protocol offers a selective and efficient route for the synthesis of a new family of chiral phosphinocyclopropane derivatives, featuring 100 % atom efficiency, good diastereo‐ and enantioselectivity, broad substrate scope, and no need for a directing group. [ABSTRACT FROM AUTHOR]

Highlights • Transition-metal-catalyzed C H bond activation has attracted substantial interest in recent years as an efficient, step-economic, and environmentally benign pathway for the synthesis of functional polymers. • The polymerization reaction may proceed through C H/C X cross-coupling, oxidative C H/C H coupling, and C H addition to unsaturated C C bonds. • C H activation may also serve as a chain transfer reaction for olefin polymerization and polymer post-functionalization. This review summarizes recent advances in this area. Abstract Transition-metal-catalyzed C H bond activation has attracted substantial interest in recent years as an efficient, step-economic, and environmentally benign pathway for the synthesis of functional polymers. The polymerization reaction may proceed through C H/C X cross-coupling, oxidative C H/C H coupling, and C H addition to unsaturated C C bonds. C H activation may also serve as a chain transfer reaction for olefin polymerization and polymer post-functionalization. This review summarizes recent advances in this area. [ABSTRACT FROM AUTHOR]

Abstract: The catalytic asymmetric construction of silicon‐stereogenic silanes is of great interest and significance, but has met with only limited success to date. We herein report the enantioselective hydrosilylation of alkenes with dihydrosilanes by a chiral half‐sandwich scandium catalyst, which constitutes an efficient and general route for the synthesis of a wide range of enantioenriched silicon‐stereogenic silanes from easily accessible starting materials. This reaction features a broad substrate scope, high yields, and high enantioselectivity. Some of the chiral tertiary silane products were also converted into valuable derivatives, such as chiral silanol, quaternary silane, and benzosilole compounds. [ABSTRACT FROM AUTHOR]

An enantioselective C−H addition to a C=C bond represents the most atom-efficient route for the construction of chiral carbon-carbon skeletons, a central research topic in organic synthesis. We herein report the enantioselective yttrium-catalyzed C(sp3)−H bond addition of 2-methyl azaarenes, such as 2-methyl pyridines, to various substituted cyclopropenes and norbornenes. This process efficiently afforded a new family of chiral pyridylmethyl-functionalized cyclopropane and norbornane derivatives in high yields and high enantioselectivities (up to 97 % ee). [ABSTRACT FROM AUTHOR]

This Review gives an overview on recent progress in the synthesis and chemistry of rare-earth metal dialkyl complexes bearing monoanionic ancillary ligands, with an emphasis on novel polymerization catalysts. These structurally well-defined and highly reactive compounds are prepared either by alkane elimination reactions between trialkyl rare-earth complexes and acidic neutral ligands, or by the metathetical reactions of rare-earth trihalides with the alkali metal salts of the corresponding ligands. On treatment with an appropriate borate compound, the dialkyl complexes are converted into the corresponding cationic monoalkyl species, which serve as excellent catalysts for the polymerization and copolymerization of a variety of olefins to yield a series of new polymer materials that exhibit novel properties. Alternatively, hydrogenation of the dialkyl rare-earth complexes with H2 affords a new class of rare-earth polyhydride complexes with unique features in terms of both their structure and reactivity. [ABSTRACT FROM AUTHOR]

The article describes the synthesis and photo- and electroluminescence properties of carbazole-substituted aromatic (E)- and (Z)-enynes. The enynes are easily prepared by catalytic dimerization of a terminal alkyne. They can act as an excellent single-emitting component for white organic light-emitting devices (WOLED), as a result of combination of the blue emission from an isolated molecule with the longer-wavelength emissions from eximers. The quality of white emission did not change under varying driving voltages, demonstrating an advantageous potential of single-emitting-component WOLED.

A graphical abstract of the study "Synthesis of Lithium Boracarbonate Ion Pairs by Copper-Catalyzed Multi-Component Coupling of Carbon Dioxide, Diboron, and Aldehydes" by B. Carry and colleagues is presented.

A combination of a half-sandwich scandium complex and [Ph3C][B(C6F5)4] catalyzes the addition reaction of diversely substituted pyridines with allenes to afford 2-alkylpyridines stereoselectively. [ABSTRACT FROM AUTHOR]

An excellent catalytic system for the ortho-selective benzylic C-H addition of various dialkyl pyridines is presented. [ABSTRACT FROM AUTHOR]