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Comprehensive Summary: A Rh(III)‐catalyzed, transmetalation triggered C—H activation/annulation of 2‐biphenylboronic acids with diazo compounds from β‐keto esters or 1,3‐dicarboxylates has been developed, leading to the synthesis of two kinds of 9,10‐phenanthrenes. Notably, a rhodacyle was synthesized by treating the rhodium catalyst with stoichiometric amounts of 2‐biphenylboronic acids and pyridine, which was further verified to be active for the catalytic system. The reactions proceeded under redox‐neutral and air‐tolerant conditions to produce a series of all‐carbon six‐membered rings with high efficiency. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Divergent synthesis of useful skeletons has been realized via rhodium(III)‐catalyzed C—H activation of iminopyridinium ylides and coupling with various unsaturated coupling reagents. Isocoumarins and isoquinolones were obtained via cleavage of the C—N or N—N bond in the ylidic directing group, while fluorinated alkenes were delivered with the directing group intact. The reactions occurred with wide substrate scopes and good efficiency under redox‐neutral and air‐tolerant conditions. Representative products exhibit solid‐state fluorescent property and bioactivity of inhibition toward human cancer cells. [ABSTRACT FROM AUTHOR]

Desymmetrization of gem‐dimethyl groups en route to the rhodium(III)‐catalyzed enantioselective sp3 C−H amidation is reported. Synthetically important β‐amino alcohol derivatives were accessed in moderate to good yields and high enantioselectivity. The high enantioselectivity is enabled by an appropriate oxime directing group, sterically biased gem‐groups in the C−H substrate, and high reactivity of the amidating reagent. [ABSTRACT FROM AUTHOR]

Reported herein is the rhodium(III)‐catalyzed C−H activation of anilines bearing an N‐isoquinolyl directing group for oxidative [3+2] annulation with four classes of internal alkynes, leading to atroposelective indole synthesis via dynamic kinetic annulation with C‐N reductive elimination constituting the stereo‐determining step. This reaction proceeds under mild conditions with high regio‐ and enantioselectivity and functional group compatibility. [ABSTRACT FROM AUTHOR]

The alkenylation reactions of 8-methylquinolines with alkynes, catalyzed by [{Cp*RhCl2}2], proceeds efficiently to give 8-allylquinolines in good yields by C(sp3)H bond activation. These reactions are highly regio- and stereoselective. A catalytically competent five-membered rhodacycle has been structurally characterized, thus revealing a key intermediate in the catalytic cycle. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Ru(II)-Catalyzed Amidation Reactions of 8-Methylquinolines with Azides via C(sp3)-H Activation" by Bingxian Liu published in the "Chemical Communications" in 2015.