Department of Chemistry , University of Illinois at Chicago , 845 W. Taylor Street, Rm. 4500 , Chicago , Illinois 60607 , United States.
J Am Chem Soc. 2019 May 22;141(20):8104-8109. doi: 10.1021/jacs.9b04189. Epub 2019 May 8.
Due to the great value of amino alcohols, new methods for their synthesis are in high demand. Abundant aliphatic alcohols represent the ideal feedstock for the method development toward this important motif. To date, transition-metal-catalyzed approaches for the directed remote amination of alcohols have been well established. Yet, they have certain disadvantages such as the use of expensive catalysts and limited scope. Very recently, transition-metal-free visible-light-induced radical approaches have emerged as new powerful tools for directed remote amination of alcohols. Relying on 1,5-HAT reactivity, these methods are limited to β - or δ-amination only. Herein, we report a novel transition-metal- and visible-light-free room-temperature radical approach for remote β -, γ-, and δ-C(sp)-N bond formation in aliphatic alcohols using mild basic conditions and readily available diazonium salt reagents.
由于氨基酸醇具有巨大的价值,因此对其合成方法的需求很高。丰富的脂肪醇是开发这一重要结构单元的理想原料。迄今为止,已建立了许多过渡金属催化的醇导向远程胺化方法。然而,它们也存在一些缺点,例如使用昂贵的催化剂和有限的适用范围。最近,无过渡金属的可见光诱导自由基方法作为醇导向远程胺化的新有力工具而出现。这些方法依赖于 1,5-HAT 反应性,仅局限于β-或δ-胺化。在此,我们报告了一种新的无需过渡金属和可见光的室温自由基方法,可在脂肪醇中温和碱性条件下,使用易得的重氮盐试剂,实现远程β-、γ-和δ-C(sp)-N 键形成。