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Abstract: The first rhodium(I)‐catalyzed enantioselective intermolecular C sp 3 –H activation of various saturated aza‐heterocycles including tetrahydroquinolines, piperidines, piperazines, azetidines, pyrrolidines, and azepanes is presented. The combination of a rhodium(I) precatalyst and a chiral monodentate phosphonite ligand is shown to be a powerful catalytic system to access a variety of important enantio‐enriched heterocycles from simple starting materials. Notably, the C sp 3 –H activation of tetrahydroquinolines is especially challenging due to the adjacent C sp 2 −H bond. This redox‐neutral methodology provides a new synthetic route to α‐N‐arylated heterocycles with high chemoselectivity and enantioselectivity up to 97 % ee. [ABSTRACT FROM AUTHOR]

Abstract: The first rhodium(I)‐catalyzed enantioselective intermolecular C sp 3 –H activation of various saturated aza‐heterocycles including tetrahydroquinolines, piperidines, piperazines, azetidines, pyrrolidines, and azepanes is presented. The combination of a rhodium(I) precatalyst and a chiral monodentate phosphonite ligand is shown to be a powerful catalytic system to access a variety of important enantio‐enriched heterocycles from simple starting materials. Notably, the C sp 3 –H activation of tetrahydroquinolines is especially challenging due to the adjacent C sp 2 −H bond. This redox‐neutral methodology provides a new synthetic route to α‐N‐arylated heterocycles with high chemoselectivity and enantioselectivity up to 97 % ee. [ABSTRACT FROM AUTHOR]

A manganese(I)/Lewis acid cocatalyzed direct C−H propargylation with high selectivity has been developed. BPh3 was discovered to not only promote the reactivity, but also enhance the selectivity. Secondary, tertiary, and even quaternary carbon centers at the propargylic position could be directly constructed. Both internal and terminal alkynes are easily accessible. The chirality was successfully transferred from an axially chiral allene to central chirality. The reactivity of the manganese catalyst in this reaction was found to be unique among transition metal catalysts. [ABSTRACT FROM AUTHOR]

A facile route toward the synthesis of isoquinolin-3-ones through a cooperative B(C6F5)3- and Cp*CoIII-catalyzed C−H bond activation of imines with diazo compounds is presented. The inclusion of a catalytic amount of B(C6F5)3 results in a highly efficient reaction, thus enabling unstable NH imines to serve as substrates. [ABSTRACT FROM AUTHOR]