During the past decades, synthetic organic chemistry discovered that directing group assisted C−H activation is a key tool for the expedient and siteselective construction of C−C bonds. Among the various directing group strategies, bidentate directing groups are now recognized as one of the most efficient devices for the selective functionalization of certain positions due to fact that its metal center permits fine, tunable, and reversible coordination. The family of bidentate directing groups permit various types of assistance to be achieved, such as N,N-dentate, N,O-dentate, and N,S-dentate auxiliaries, which are categorized based on the coordination site. In this review, we broadly discuss various C− H bond functionalization reactions for the formation of C−C bonds with the aid of bidentate directing groups.

In recent years, transition‐metal‐catalyzed C−H activation has become a key strategy in the field of organic synthesis. Rhodium complexes are widely used as catalysts in a variety of C−H functionalization reactions because of their high reactivity and selectivity. The availability of a number of rhodium complexes in various oxidation states enables diverse reaction patterns to be obtained. Regioselectivity, an important issue in C−H activation chemistry, can be accomplished by using a directing group to assist the reaction. However, to obtain the target functionalized compounds, it is also necessary to use a directing group that can be easily removed. A wide range of directed C−H functionalization reactions catalyzed by rhodium complexes have been reported to date. In this Review, we discuss Rh‐catalyzed C−H functionalization reactions that are aided by the use of a removable directing group such as phenol, amine, aldehyde, ketones, ester, acid, sulfonic acid, and N‐heteroaromatic derivatives.

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Hydroboration of alkynes is of special interest to researchers since it is the most straightforward process for the synthesis of highly important vinylborane synthetic intermediate compounds. It is significant in terms of both regioselectivity and stereoselectivity, since several positional isomers are formed during the process of hydroboration. Given the importance of this class of compounds, an extensive study has been carried out regarding catalytic condition development and detailed mechanistic studies for selectively obtaining a single isomer. This review comprehensively summarizes both the regioselective and stereoselective catalytic hydroboration of alkynes. It is aimed at giving readers accurate knowledge of the catalytic systems available for the hydroboration of certain alkynes. We anticipate that this inclusive review will encourage researchers to explore more new types of catalytic systems to achieve the remarkable process of hydroboration of alkynes.

The rhodium(I)-catalyzed C−H alkylation of 1naphthylamide derivatives with alkenes at the C8-position using a picolinamide directing group is reported. Various alkenes including styrene derivatives, α,β-unsaturated carbonyl compounds, and even unactivated alkene could also be used as coupling partners. The reaction mechanism was investigated in kinetic studies, deuterium labeling studies, and control experiments. The reaction appears to proceed through a rhodium carbene intermediate, which is generated from an alkene.