Cobaltacycle synthesis via C-H activation has been achieved for the first time, providing key mechanistic insight into cobalt catalytic chemistry. N-Chloroamides are used as a directing synthon for cobalt-catalyzed room-temperature C-H activation and construction of heterocycles. Alkynes as coupling partners allow convenient access to isoquinolones, a class of synthetically and pharmaceutically important compounds. The broad substrate scope enables a diverse range of substitution patterns to be incorporated into the heterocyclic scaffold.

We describe herein a fundamentally new visible lightdriven homolytic C−C bond breaking mode for the generation of acyl radicals from C2-acyl-substituted benzothiazolines. The reactive species can be used as versatile synthons for formal radical alkylation, alkenylation, and alkynylation reactions.

Rh(III)-catalyzed enaminone-directed C-H coupling with α-diazo-α-phosphonoacetate has been used for the identification of fluoride-mediated dephosphonation C-C coupling reactivity for the synthesis of 4-hydroxy-1-naphthoates. Intermolecular C-C coupling of α-phosphonoacetate and benzaldehyde for ( E)-selective α,β-unsaturated ester synthesis has also been achieved.