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Transition metal catalyzed decarbonylation offers a distinct synthetic strategy for new chemical bond formation. However, the π‐backbonding between CO π* orbitals and metal center d‐orbitals impedes ligand dissociation to regenerate the catalyst under mild reaction conditions. Developed here is visible light induced rhodium catalysis for decarbonylative coupling of imides with alkynes under ambient conditions. Initial mechanistic studies suggest that the rhodium complex simultaneously serves as the catalytic center and photosensitizer for decarbonylation. This visible light promoted catalytic decarbonylation strategy offers new opportunities for reviewing old transformations with ligand dissociation as a rate‐determining step. [ABSTRACT FROM AUTHOR]

The direct CH annulation of anilines or related compounds with internal alkynes provides straightforward access to 2,3-disubstituted indole products. However, this transformation proceeds with poor regioselectivity in the synthesis of unsymmetrically 2,3-diaryl substituted indoles. Herein, we report the rhodium(III)-catalyzed CH annulation of nitrones with symmetrical diaryl alkynes as an alternative method to prepare 2,3-diaryl-substituted N-unprotected indoles with two different aryl groups. One of the aryl substituents is derived from NC-aryl ring of the nitrone and the other from the alkyne substrate, thus providing the indole products with exclusive regioselectivity. [ABSTRACT FROM AUTHOR]

Rh(III)-catalyzed,chelation-assisted C–H activation and selenylation of areneshas been achieved. Arenes bearing oxime, azo, pyridyl, and N-oxide chelating groups are viable substrates, and electrophilicselenyl chlorides and diselenides are used as selenylating reagents.The catalytic system is highly efficient under mild conditions overa broad range of substrates with excellent functional group tolerance. [ABSTRACT FROM AUTHOR]

N-aryl-substituted nitrones were employed as five-atom coupling partners in the rhodium-catalyzed cyclization with diynes. In this reaction, the nitrone moiety served as a directing group for the catalytic CH activation of the N-aryl ring. This formal [2+2+5] approach allows rapid access to bridged eight-membered heterocycles with broad substrate scope. The results of this study may provide new insight into the chemistry of nitrones and find applications in the synthesis of other heterocycles. [ABSTRACT FROM AUTHOR]

Rhodium(III)-catalyzed C–H activation–amidation of arenes bearing chelating groups has been achieved using N-arenesulfonated imides as efficient amidating reagents without using any base additive. Pyridine, oxime, and pyrimidine proved to be viable directing groups. [ABSTRACT FROM AUTHOR]

Two alternative, simple procedures for the Rh(III)-catalyzed selenylation of arenes bearing a directing group (29 examples) are developed. [ABSTRACT FROM AUTHOR]

N-Phenyl-α-arylnitrones react with symmetrical dialkylacetylenes to form unsymmetrically 2,3-diaryl-substituted N-unprotected indole derivatives in moderate to often high yields. The scalable, regioselective reaction is applicable to dialkylacetylenes and tolerates diverse functional groups. [ABSTRACT FROM AUTHOR]

A diagram is presented showing the activation of rhodium-catalyst of carbon-hydrogen (C-H) of phenacyl ammonium salts helped by an oxidizing carbon nitrogen (C-N) bond.

A new route for the preparation of title compounds such as (III) and (V) via [2+2+2] cycloaddition of various diynes (I) and oximes using [Rh(nbd)2]BF4/MeO-Bipheb as catalyst. [ABSTRACT FROM AUTHOR]

Sterically hindered aryl boronic acids, e.g. (IIf), and boronic acids bearing electron-withdrawing substituents, e.g. (IIe), do not affect the stereoselectivity, however have a significant effect on the reactivity. [ABSTRACT FROM AUTHOR]

A regioselective C-C coupling between N-sulfonyl-substituted aziridines and electron-poor arenes, substituted with an N-heteroaromatic directing group, is achieved under optimized conditions for a broad spectrum of substrates. [ABSTRACT FROM AUTHOR]