2909-84-4Relevant articles and documents
Tertiary butylation of aniline over nanosized zeolite beta catalyst
Radhika,Selvin, Rosilda,Kakkar, Rita,Selva Roselin,Hsu, Hsiu-Ling
, p. 7960 - 7968 (2018)
In the current paper, we report nanosized zeolite beta to be a robust and potent catalyst for tertbutylation of aniline. Nanocrystals of beta zeolite having spherical morphology were prepared via a one-pot strategy that is based on vacuum-concentration coupled hydrothermal method. The catalyst could be used in the as-synthesized form, without any further modifications. In the presence of the as-prepared catalyst, liquid-phase tert-butylation of aniline using tert-butanol as alkylating agent proceeded successfully. Reaction parameters like duration of reaction, temperature, mole ratio of substrates and quantity of catalyst were optimized. Time-dependent data obtained was subjected to kinetic studies. Detailed studies on product selectivity were conducted. The catalyst could selectively direct the formation of C–C bonds and no N-alkylated products were detected. It also demonstrated good selectivity towards mono-substitution. The catalyst could be recovered by a simple work-up plan and could then be re-used. No appreciable loss in activity was detected in consecutive runs. Thus, the nanosized beta mediated route to introduce tert-butyl group on aniline ring can be an environment-friendly alternative to the use of homogeneous catalysts.
A Metal-Free Direct Arene C?H Amination
Wang, Tao,Hoffmann, Marvin,Dreuw, Andreas,Hasagi?, Edina,Hu, Chao,Stein, Philipp M.,Witzel, Sina,Shi, Hongwei,Yang, Yangyang,Rudolph, Matthias,Stuck, Fabian,Rominger, Frank,Kerscher, Marion,Comba, Peter,Hashmi, A. Stephen K.
supporting information, p. 2783 - 2795 (2021/04/05)
The synthesis of aryl amines via the formation of a C?N bond is an essential tool for the preparation of functional materials, active pharmaceutical ingredients and bioactive products. Usually, this chemical connection is only possible by transition metal-catalyzed reactions, photochemistry or electrochemistry. Here, we report a metal-free arene C?H amination using hydroxylamine derivatives under benign conditions. A charge transfer interaction between the aminating reagents TsONHR and the arene substrates enables the chemoselective amination of the arene, even in the presence of various functional groups. Oxygen was crucial for an effective conversion and its accelerating role for the electron transfer step was proven experimentally. In addition, this was rationalized by a theoretical study which indicated the involvement of a dioxygen-bridged complex with a “Sandwich-like” arrangement of the aromatic starting materials and the aminating agents at the dioxygen molecule. (Figure presented.).
Electrochemical Amination of Less-Activated Alkylated Arenes Using Boron-Doped Diamond Anodes
Herold, Sebastian,M?hle, Sabine,Zirbes, Michael,Richter, Frank,Nefzger, Hartmut,Waldvogel, Siegfried R.
supporting information, p. 1274 - 1278 (2016/03/19)
The anodic C-H amination of aromatic compounds is a powerful and versatile method for the synthesis of aniline derivatives. By using boron-doped diamond (BDD) anodes, a method initially described by Yoshida et al. for electron-rich arenes was expanded to less-activated aromatic systems e.g., simple alkylated benzene derivatives. Anodes based on sp3 carbon seem to be the key for the electrochemical amination reaction. The corresponding primary anilines are obtained in good yields. Despite the cationic intermediates of the electrolytic reaction tert-butyl moieties are tolerated.
