Rhodium(III)‐Catalyzed Annulation of Azomethine Ylides with Alkynes via CH Activation

Abstract

The rhodium(III)‐catalyzed coupling of azomethine ylides with alkynes via CH activation has been developed for the synthesis of indenamines in moderate to high yields. The coupled products can be further oxidized to indenones and derivatives.

Rhodium(III)-Catalyzed Redox-Neutral Synthesis of Isoquinolinium Salts via C–H Activation of Imines

“…As a common bifunctional DG, imine bears both electrophilic carbon and nucleophilic nitrogen sites and has been widely used in C–H activation. Cheng, Miura, Zhao, and our group have reported [3 + 2] coupling of imines with alkynes by taking advantage of the electrophilicity of imines. On the other hand, while the nucleophilicity of protic NH DGs in postcoupling C–H annulation is well-known, N -substituted imines only occasionally participated in annulative N–C coupling, which led to ammonium salt formation .…”

Redox-Neutral Couplings between Amides and Alkynes via Cobalt(III)-Catalyzed C–H Activation

“…Electrophilic DGs are bifunctional in that they consist of a nucleophilic coordinating site and an electrophilic center. This discrepancy has been reconciled in recent work by Cheng, Glorius, Shi, and others in Rh­(III)-catalyzed C–H activation. However, reports in this regard remain limited, particularly in the context of heterocycle synthesis …”

Rh(III)- and Ir(III)-Catalyzed C–C Bond Cross Couplings from C–H Bonds

“…Finally, an electrophilic character of several DGs such as ketones [61], urea [62], azomethine ylides [63], or tertiary benzamides [64] is another appealing feature. As a Rh-C(alkenyl) bond, generated via migratory insertion of an alkyne into a Rh-C bond, may be considered as a nucleophile, an intramolecular addition to such an electrophilic moiety as the directing group can be envisioned (5).…”