CONSPECTUS In recent years, carbon–hydrogen bond functionalization has evolved from an organometallic curiosity to mainstream applications in the synthesis of complex natural products and drugs. The use of C–H bonds as a transformable functional group is advantageous because these bonds are the most abundant functionality in organic molecules. One-step conversion of these bonds to the desired functionality shortens synthetic pathways, saving reagents, solvents, and labor. Less chemical waste is generated as well, showing that this chemistry is environmentally beneficial. This Account describes the development and use of bidentate, monoanionic auxiliaries for transition-metal-catalyzed C–H bond functionalization reactions. The chemistry was initially developed to overcome the limitations with palladium-catalyzed C–H bond functionalization assisted by monodentate directing groups. By the use of electron-rich bidentate directing groups, functionalization of unactivated sp3 C–H bonds under palladium catalysis has been developed. Furthermore, a number of abundant base-metal complexes catalyze functionalization of sp2 C–H bonds. At this point, aminoquinoline, picolinic acid, and related compounds are among the most used and versatile directing moieties in C–H bond functionalization chemistry. These groups facilitate catalytic functionalization of sp2 and sp3 C–H bonds by iron, cobalt, nickel, copper, ruthenium, rhodium, and palladium complexes. Exceptionally general reactivity is observed, enabling, among other transformations, direct arylation, alkylation, fluorination, sulfenylation, amination, etherification, carbonylation, and alkenylation of carbon–hydrogen bonds. The versatility of these auxilaries can be attributed to the following factors. First, they are capable of stabilizing high oxidation states of transition metals, thereby facilitating the C–H bond functionalization step. Second, the directing groups can be removed, enabling their use in synthesis and functionalization of natural products and medicinally relevant substances. While the development of these directing groups presents a significant advance, several limitations of this methodology are apparent. The use of expensive second-row transition metal catalysts is still required for efficient sp3 C–H bond functionalization. Furthermore, a disadvantage is the need to install and subsequently remove the relatively expensive directing group.

Amine meets arene: A method for direct amination of β‐C(sp2)H bonds of benzoic acid derivatives and γ‐C(sp2)H bonds of benzylamine derivatives has been developed. The reaction is catalyzed by Cu(OAc)2 and a Ag2CO3 cocatalyst, and shows high generality and functional‐group tolerance, as well as providing a straightforward means for the preparation of ortho‐aminobenzoic acid derivatives.

A method for direct, auxiliary-assisted alkoxylation and phenoxylation of β-sp2 C−H bonds of benzoic acid derivatives and γ-sp2 C−H bonds of amine derivatives is reported. The reaction employs (CuOH)2CO3 catalyst, air as an oxidant, phenol or alcohol coupling partner, DMF, pyridine, or DMPU solvent, and K2CO3, tetramethylguanidine, or K3PO4 base at 90–130 °C.

An operationally simple and general method for copper-catalyzed, aminoquinoline-assisted amination of β-C(sp2)-H bonds of benzoic acid derivatives is reported. The reaction employs Cu(OAc)2 or (CuOH)2CO3 catalysts, an amine coupling partner, and oxygen from air as a terminal oxidant. Exceptionally high generality with respect to amine coupling partners is observed. Specifically, primary and secondary aliphatic and aromatic amines, heterocycles, such as indoles, pyrazole, and carbazole, sulfonamides, as well as electron-deficient aromatic and heteroaromatic amines are competent coupling components.

Amine meets arene: A method for direct amination of β‐C(sp2)H bonds of benzoic acid derivatives and γ‐C(sp2)H bonds of benzylamine derivatives has been developed. The reaction is catalyzed by Cu(OAc)2 and a Ag2CO3 cocatalyst, and shows high generality and functional‐group tolerance, as well as providing a straightforward means for the preparation of ortho‐aminobenzoic acid derivatives.