A Direct Access to 7-Aminoindoles via Iridium-Catalyzed Mild C–H Amidation of N-Pivaloylindoles with Organic Azides

Abstract

Ir(III)-catalyzed regioselective direct C-7 amidation of indoles in reaction with organic azides has been developed. While its efficiency was varied by the choice of N-directing groups, N-pivaloylindoles were most effective in undergoing the desired amidation at room temperature over a broad range of substrates. The reaction was scalable, and deprotection of the chelation group was also facile.

Iridium‐Catalyzed Direct C4‐ and C7‐Selective Alkynylation of Indoles Using Sulfur‐Directing Groups

“…Intriguingly, the desired C7‐alkynylated indole 9 a was obtained in 65 % yield after the basic treatment of the crude reaction mixture, and no competing reaction on the pyrrole ring was observed. Other directing groups used in previous reports for the C7‐selective reactions, pivaloyl, phosphine, and phosphine oxide, were ineffective in the present alkynylation protocol.…”

Cu‐Catalyzed Directed C7−H Imidation of Indolines via Cross‐Dehydrogenative Coupling

“…Subsequently, Chang et al. disclosed a better variant of this protocol using not only with the sulfonyl azides, but also with aryl, and alkyl azides, albeit using Ir‐catalyst . Importantly, the reaction occurred at room temperature, delivering products with excellent yields even with the substrates that contain readily removable N ‐ protecting groups.…”

Advance in C-H Arylation of Indoles

“…游 劲松 [48] 和 Chupakhin 课题组 [49] 分别使用了 N-甲基咪唑 衍生物和 N-氧化咪唑衍生物作为芳基化试剂实现了吲 哚 C3 位的芳基化(Eqs. 25,26). 3 吲哚 C2 位 C-H 芳基化 3.1 Pd 催化吲哚 C2 位 C-H 芳基化 在过去的几年中, 有机化学家对吲哚 C2 位的 C-H 键芳基化进行了大量地研究, 尤其是 Pd 催化的吲哚 C2 位 C-H 芳基化的方法相继被报道.…”