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The synthesis and photophysical properties of a soluble amide‐embedded coronene is reported. The key step in this synthesis is the twofold C−H activation of diazaperylene by a rhodium(III)Cp* catalyst. This unprecedented structural motif shows intense fluorescence in the near infrared region with a small Stokes shift and a distinct vibronic structure, which exhibits a slight extent of negative solvatochromism. Comparison of this compound with some relevant compounds revealed the importance of the amide incorporation in the peripheral concave region including an angular position to retain high aromaticity reflecting that of parent coronene. Treatment of this compound with Lewis acid B(C6F5)3 formed a bis‐adduct, which exhibited enhanced aromaticity as a consequence of the increased double bond character of the amide C−N bonds. [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]

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: An unprecedented MnI‐catalyzed (2‐indolyl)methylation of heteroarenes is reported. This method makes use of an aromatizing cascade strategy to install a (2‐indolyl)methyl group into target molecules, thereby leading to the expedient synthesis of previously challenging and important unsymmetrical diheteroarylmethanes, in particular bis(2‐indolyl)methanes. The proposed cascade process comprises the reorganization of multiple bonds with controlled regioselectivity and high atom economy and can be performed on a gram‐scale. Furthermore, a metal‐free C−H propargylation is observed. The diverse application of this method is also demonstrated. [ABSTRACT FROM AUTHOR]

A strategy is reported in which traceless directing groups (TDGs) are used to promote the redox-neutral MnI-catalyzed regioselective synthesis of N-heterocycles. Alkyne coupling partners bearing a traceless directing group, which serves as both the chelator and internal oxidant, were used to control the regioselectivity of the annulation reactions. This operationally simple approach is highly effective with previously challenging unsymmetrical alkyne systems, including unbiased dialkyl alkynes, with perfect regioselectivity. The simple conditions and the ability to carry out synthesis on a gram scale underscore the usefulness of this method. The application of this strategy in the concise synthesis of the bioactive compound PK11209 and the pharmaceutical moxaverine is also described. [ABSTRACT FROM AUTHOR]

A MnI-catalyzed regioselective C−H allenylation is reported that allows a broad range of 2-allenylindoles to be synthesized regioselectively on a gram scale under simple conditions. Notably, a highly efficient chirality transfer was observed (up to 93 % ee) in this transformation. This procedure was further found to allow, for the first time, the direct preparation of ketones by MnI-catalyzed C−H activation. Mechanistic investigations revealed that the precoordination of the oxygen atom to the manganese center as well as the congested tertiary carbon atom in the propargylic carbonates play a crucial role. [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]