Rhodium(III)‐Catalyzed Amidation of Unactivated C(sp³)H Bonds

Abstract

Nitrogenation by direct functionalization of C-H bonds represents an important strategy for constructing C-N bonds. Rhodium(III)-catalyzed direct amidation of unactivated C(sp(3) )-H bonds is rare, especially under mild reaction conditions. Herein, a broad scope of C(sp(3) )-H bonds are amidated under rhodium catalysis in high efficiency using 3-substituted 1,4,2-dioxazol-5-ones as the amide source. The protocol broadens the scope of rhodium(III)-catalyzed C(sp(3) )-H activation chemistry, and is applicable to the late-stage functionalization of natural products.

Cp*CoIII‐Catalyzed C(sp3)−H Bond Amidation of 8‐Methylquinoline

“…Based on the above experiments and the relevantr eportso nC (sp 3 )ÀHb ond amidation using Rh III and Ir III catalysts, [19] ap lausible mechanism is proposed (Scheme 5). Cationicc omplex A undergoes irreversible externalb ase-assisted CÀHb ond activation leading to cobalt metallacycle B in the presence of excesso fN aOPiv.…”

Anthranil: An Aminating Reagent Leading to Bifunctionality for Both C(sp3)−H and C(sp2)−H under Rhodium(III) Catalysis

“…[2] In addition to the Buchwald-Hartwig [3] and the Chan-Lam aminations, [4] direct amination of C À Hb onds constitutes an ideal protocol. [6] However,o nly limited examples of C(sp 3 )ÀHa mination/ amidation [7] have been reported using azides, [8] amides, [9] NFSI, [10] 1,4,2-dioxazol-5-ones, [11] and O-benzoyl hydroxylmorpholine [12] as nitrogen sources (Scheme 1a). [6] However,o nly limited examples of C(sp 3 )ÀHa mination/ amidation [7] have been reported using azides, [8] amides, [9] NFSI, [10] 1,4,2-dioxazol-5-ones, [11] and O-benzoyl hydroxylmorpholine [12] as nitrogen sources (Scheme 1a).…”

“…[6] However,o nly limited examples of C(sp 3 )ÀHa mination/ amidation [7] have been reported using azides, [8] amides, [9] NFSI, [10] 1,4,2-dioxazol-5-ones, [11] and O-benzoyl hydroxylmorpholine [12] as nitrogen sources (Scheme 1a). [11] Recently Chang and co-workers reported the amidation of arenes using 1,4,2-dioxazol-5-ones as versatile amidating reagents with the loss of CO 2 . [11] Recently Chang and co-workers reported the amidation of arenes using 1,4,2-dioxazol-5-ones as versatile amidating reagents with the loss of CO 2 .…”

“…2-Isopropylpyridine,w hich failed to undergo C À Hactivation in previous studies, [11] coupled smoothly with various anthranils,t hus leading to desymmetrization in good to high yields (4aa-ai). Thea mination reaction was been extended to 3-substituted anthranils,thus affording the desired product with apendent ketone group (3ai and 3aj).…”

Rapid Microwave‐Assisted, Solvent‐Free Approach to Functionalization of 8‐Methylquinolines via Rh‐Catalyzed C(sp3)‐H Activation

“…To gain further insight into the reaction mechanism, the kinetic isotope effect (KIE) experiments between 1a and [D 3 ]‐ 1a were performed according to previous report (Scheme ). Both parallel and competition reactions afforded similar KIE results (KIE = 9.0).…”