Regiodivergent C-H and Decarboxylative C-C Alkylation by Ruthenium Catalysis: ortho versus meta Position-Selectivity.

Ruthenium(II)biscarboxylate complexes enabled the selective alkylation of C-H and C-C bonds at the ortho- or meta-position. ortho-C-H Alkylations were achieved with 4-, 5- as well as 6-membered halocycloalkanes. Furthermore, the judicious choice of the directing group allowed for a full control of ortho-/meta-selectivities. Detailed mechanistic studies by experiment and computation were performed and provided strong support for an oxidative addition/reductive elimination process for ortho-alkylations, while a homolytic C-X cleavage was operative for the meta-selective transformations.

Ruthenium(II)-Catalyzed C-C Arylations and Alkylations: Decarbamoylative C-C Functionalizations.

Ruthenium(II)biscarboxylate catalysis enabled selective C-C functionalizations by means of decarbamoylative C-C arylations. The versatility of the ruthenium(II) catalysis was reflected by widely applicable C-C arylations and C-C alkylations of aryl amides, as well as acids with modifiable pyrazoles, through facile organometallic C-C activation.

C-H alkenylations with alkenyl acetates, phosphates, carbonates, and carbamates by cobalt catalysis at 23 °C.

Inexpensive cobalt catalysts with N-heterocyclic carbene ligands enable direct arene alkenylations with easily accessible alkenyl acetates through regioselective C-H/C-O functionalizations in a stereoconvergent fashion. The versatile cobalt catalyst was broadly applicable and thus also allowed for the efficient conversion of alkenyl phosphates, carbonates, and carbamates at ambient temperature.