Stibine-catalyzed selective conversion of nitroarenes to hydroxylanilines through deoxygenation and hydroboration
Lu Zhao1, Zichen Zhang1, Kunlong Li1
1Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610065, China. zhoujiliang@scu.edu.cn.
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We accomplish the synthesis of hydroxylanilines, which usually serve as transient intermediates in nitro reduction, directly from nitroarenes by employing HBpin as the reductant and a simple stibine (nBu3Sb) as the catalyst, demonstrating the unique chemoselectivity of antimony redox catalysis. Mechanistic investigations reveal that the transformation proceeds through relay deoxygenation and hydroboration processes via distinct SbIII/SbV cycling, highlighting the diverse redox reactivity of antimony catalysts.
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