The invention relates to the use of quinoxaline derivatives as photostable UV filters in cosmetic and pharmaceutical preparations for protecting the human epidermis or human hair against UV radiation, especially in the 280-400 nm range.
Hydrogen Auto‐transfer Synthesis of Quinoxalines from
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‐Nitroanilines and Biomass‐based Diols Catalyzed by MOF‐derived N,P Co‐doped Cobalt Catalysts
作者:Kangkang Sun、Dandan Li、Guo‐Ping Lu、Chun Cai
DOI:10.1002/cctc.202001362
日期:2021.1.12
A Co‐based heterogeneous catalyst supported on N,P co‐doped porous carbon (Co@NCP) is prepared via a facile in‐situ doping‐carbonization method. The Co@NCP composite features a large surface area, high pore volume, high‐density and strong basic sites. Furthermore, doping of P atoms can regulate the electronic density of Co. Therefore, Co@NCP exhibits good performance for the synthesis of quinoxalines
Application of a reusable Co-based nanocatalyst in alcohol dehydrogenative coupling strategy: Synthesis of quinoxaline and imine scaffolds
作者:Dibyajyoti Panja、Bhaskar Paul、Bhuvaneshwari Balasubramaniam、Raju K. Gupta、Sabuj Kundu
DOI:10.1016/j.catcom.2020.105927
日期:2020.4
efficient synthesis of imines and quinoxaline motifs is reported. Co(OAc)2-Phen/Carbon-800 (Co-phen/C-800) showed the superior reactivity compared to other materials prepared at different temperature, in the synthesis of quinoxalines by the coupling between diamines and diols. Moreover, applying the transfer hydrogenation and acceptorlessdehydrogenative coupling strategy, imines and quinoxaline derivatives
Asymmetric Hydrogenation of 2- and 2,3-Substituted Quinoxalines with Chiral Cationic Ruthenium Diamine Catalysts
作者:Jie Qin、Fei Chen、Ziyuan Ding、Yan-Mei He、Lijin Xu、Qing-Hua Fan
DOI:10.1021/ol2029096
日期:2011.12.16
The enantioselective hydrogenation of 2-alkyl- and 2-aryl-subsituted quinoxalines and 2,3-disubstituted quinoxalines was developed by using the cationic Ru(η6-cymene)(monosulfonylated diamine)(BArF) system in high yields with up to 99% ee. The counteranion was found to be critically important for the high enantioselectivity and/or diastereoselectivity.
Nickel-Catalyzed Direct Synthesis of Quinoxalines from 2-Nitroanilines and Vicinal Diols: Identifying Nature of the Active Catalyst
作者:Sujan Shee、Dibyajyoti Panja、Sabuj Kundu
DOI:10.1021/acs.joc.9b03104
日期:2020.2.21
The inexpensive and simple NiBr2/1,10-phenanthroline system-catalyzed synthesis of a series of quinoxalinesfrom both 2-nitroanilines and 1,2-diamines is demonstrated. The reusability test for this system was performed up to the seventh cycle, which afforded good yields of the desired product without losing its reactivity significantly. Notably, during the catalytic reaction, the formation of the heterogeneous