3169-62-8Relevant academic research and scientific papers
Zeolite catalyzed hydroarylation of alkenes with aromatic amines under organic ligand-free conditions
Li, Teng,Liu, Shujuan,Shi, Feng,Wang, Hongli,Wang, Xinzhi,Yuan, Hangkong,Zhao, Kang
, p. 18 - 29 (2021/01/12)
The hydroarylation of alkenes with aromatic amines is recognized as the most atom-economical and straightforward approach to obtain functional aromatic amines, which are versatile building blocks in organic synthesis and material chemistry. However, controllable synthesis of single hydroarylation product is still a significant challenge because hydroarylation reaction often delivers four hydroarylation products and hydroamination products are also produced during the reaction. Herein, we report the first example of heterogeneous zeolite catalyzed hydroarylation of styrene and norbornene with aniline derivatives under organic ligand-free conditions. With the USY zeolite as catalyst, a wide scope of alkenes and aromatic amines with various functional groups are smoothly converted into the corresponding products in 48–95% yields with high regioselectivity. Detailed characterizations revealed that Lewis acid can promote Hofmann-Martius rearrangement of hydroamination products toward hydroarylation products, resulting in high selectivity for hydroarylation products. In addition, it could be found that the weak acid sites of zeolite play a key role in forming hydroarylation products. Furthermore, the catalyst can be reused at least 10 times without obvious deactivation. This work may promote the development of heterogeneous catalyst system for alkene hydroarylation.
On the Superior Activity of In(I) versus In(III) Cations Toward ortho-C-Alkylation of Anilines and Intramolecular Hydroamination of Alkenes
Li, Zhilong,Yang, Shengwen,Thiery, Guillaume,Gandon, Vincent,Bour, Christophe
, p. 12947 - 12959 (2020/11/23)
An efficient ortho-C-alkylation of unprotected anilines with a variety of styrenes and alkenes using a univalent cationic indium(I) catalyst is reported. Mechanistic studies revealed that the reaction likely proceeds via a tandem hydroamination/Hofmann-Martius rearrangement. The high compatibility between the cationic indium(I) complex and primary anilines led us to develop an In(I)+-catalyzed hydroamination of alkenes using unprotected primary and secondary alkenylamines. Computations support the catalytic activity of naked In(I)+ ions, with an outer sphere mechanism for the C-N bond formation and a potentially inner sphere protodemetallation.
