Institut für Organische Chemie , Universität Leipzig , Johannisallee 29 , D-04103 Leipzig , Germany.
J Org Chem. 2018 Apr 6;83(7):3738-3745. doi: 10.1021/acs.joc.8b00096. Epub 2018 Mar 15.
Orthogonal protection and deprotection of amines remain important tools in synthetic design as well as in chemical biology and material research applications. A robust, highly efficient, and sustainable method for the formation of phenacyl-based carbamate esters was developed using CO for the in situ preparation of the intermediate carbamates. Our mild and broadly applicable protocol allows for the formation of phenacyl urethanes of anilines, primary amines, including amino acids, and secondary amines in high to excellent yields. Moreover, we demonstrate the utility by a mild and convenient photocatalytic deprotection protocol using visible light. A key feature of the Ru(bpy)-catalyzed method is the use of ascorbic acid as reductive quencher in a neutral, buffered, two-phase acetonitrile/water mixture, granting fast and highly selective deprotection for all presented examples.
胺的正交保护和脱保护仍然是合成设计以及化学生物学和材料研究应用中的重要工具。我们开发了一种使用 CO 原位制备中间氨基甲酸酯的方法，用于形成基于苯乙酮的氨基甲酸酯酯，该方法具有高稳定性、高效率和可持续性。我们温和且广泛适用的方案允许苯胺、伯胺（包括氨基酸）和仲胺的苯乙酮尿烷以高至优异的产率形成。此外，我们通过使用可见光的温和且方便的光催化脱保护方案证明了其实用性。[Ru(bpy)]（PF）-催化方法的一个关键特点是在中性、缓冲的两相乙腈/水混合物中使用抗坏血酸作为还原猝灭剂，为所有呈现的实例提供快速且高度选择性的脱保护。
