https://pubs.rsc.org/en/content/articlepdf/2019/NP/C8NP00092A

Marine natural products.

The direct functionalization of C-H bonds in organic compounds has recently emerged as a powerful and ideal method for the formation of carbon-carbon and carbon-heteroatom bonds. This Review provides an overview of C-H bond functionalization strategies for the rapid synthesis of biologically active compounds such as natural products and pharmaceutical targets.

C-H bond functionalization: emerging synthetic tools for natural products and pharmaceuticals

Ruthenium(II)-Catalyzed C–H Bond Activation and Functionalization

C-H bonds are ubiquitous in organic compounds. It would, therefore, appear that direct functionalization of substrates by activation of C-H bonds would eliminate the multiple steps and limitations associated with the preparation of functionalized starting materials. Regioselectivity is an important issue because organic molecules can contain a wide variety of C-H bonds. The use of a directing group can largely overcome the issue of regiocontrol by allowing the catalyst to come into proximity with the targeted C-H bonds. A wide variety of functional groups have been evaluated for use as directing groups in the transformation of C-H bonds. In 2005, Daugulis reported the arylation of unactivated C(sp(3))-H bonds by using 8-aminoquinoline and picolinamide as bidentate directing groups, with Pd(OAc)2 as the catalyst. Encouraged by these promising results, a number of transformations of C-H bonds have since been developed by using systems based on bidentate directing groups. In this Review, recent advances in this area are discussed.

Catalytic Functionalization of C(sp2) ? H and C(sp3) ? H Bonds by Using Bidentate Directing Groups

Pd-catalyzed cross-coupling reactions that form C–N bonds have become useful methods to synthesize anilines and aniline derivatives, an important class of compounds throughout chemical research. A key factor in the widespread adoption of these methods has been the continued development of reliable and versatile catalysts that function under operationally simple, user-friendly conditions. This review provides an overview of Pd-catalyzed N-arylation reactions found in both basic and applied chemical research from 2008 to the present. Selected examples of C–N cross-coupling reactions between nine classes of nitrogen-based coupling partners and (pseudo)aryl halides are described for the synthesis of heterocycles, medicinally relevant compounds, natural products, organic materials, and catalysts.

Applications of Palladium-Catalyzed C–N Cross-Coupling Reactions

Sulfinic acids and their salts have recently emerged as versatile coupling partners to efficiently access a wide variety of hetero- and carbocyclic compounds, under relatively mild conditions. Their growing importance is attributable to their dual capacity for acting as nucleophilic or electrophilic reagents. This report summarizes recent advances in the preparation and use of sulfinates in organic synthesis.

Sulfinate derivatives: dual and versatile partners in organic synthesis

Herein is reported a convergent synthesis of isocombretastatins A, a novel class of potent antitubulin agents. These compounds having a 1,1-diarylethylene scaffold constitute the simplest isomers of natural Z-combretastatins A that are easy to synthesize without need to control the Z-olefin geometry. The discovery of isoCA-4 with biological activities comparable to that of CA-4 represents a major progress in this field.

Isocombretastatins a versus combretastatins a: the forgotten isoCA-4 isomer as a highly promising cytotoxic and antitubulin agent.

Transition-Metal-Catalyzed Direct C–H Alkenylation, Alkynylation, Benzylation, and Alkylation of (Hetero)arenes

Palladium(II)-Catalyzed Oxidative Arylation of Quinoxalin-2(1H)-ones with Arylboronic Acids

New approaches to the Pd-catalysis employing palladacycle precatalysts have been recently developed. Breakthroughs in this area using 2-aminobiphenyl palladacycle precatalysts are highlighted. High reactivity and selectivity are achieved for the C–C and C–heteroatom bond formation under mild reaction conditions.

Samir Messaoudi

Papers

Sulfinate derivatives: dual and versatile partners in organic synthesis

Isocombretastatins a versus combretastatins a: the forgotten isoCA-4 isomer as a highly promising cytotoxic and antitubulin agent.

Transition-Metal-Catalyzed Direct C–H Alkenylation, Alkynylation, Benzylation, and Alkylation of (Hetero)arenes

Palladium(II)-Catalyzed Oxidative Arylation of Quinoxalin-2(1H)-ones with Arylboronic Acids

2-Aminobiphenyl Palladacycles: The “Most Powerful” Precatalysts in C–C and C–Heteroatom Cross-Couplings