Photoredox‐Catalyzed Site‐Selective α‐C(sp
<sup>3</sup>
)−H Alkylation of Primary Amine Derivatives
作者:Melissa A. Ashley、Chiaki Yamauchi、John C. K. Chu、Shinya Otsuka、Hideki Yorimitsu、Tomislav Rovis
DOI:10.1002/anie.201812227
日期:2019.3.18
tertiary amines to oxidatively generate α‐amino radicals is well established, however, primary amines remain challenging because of competitive side reactions. This report describes the site‐selective α‐functionalization of primary amine derivatives through the generation of α‐amino radical intermediates. Employing visible‐light photoredoxcatalysis, primary sulfonamides are coupled with electron‐deficient
Implementing the “Catch-and-Release” Concept into a Simple Method for Regioselective Cyclodextrin Modification
作者:Iris Pflueger、Juan M. Benito
DOI:10.1021/ol400641n
日期:2013.5.17
Differentiation of specific positions in axial-symmetrical cyclodextrins (CDs), exhibiting a dense display of identical functional groups, is challenging. A novel strategy toward this goal that exploits a solid matrix to display the complementary reagent functionalities sufficiently far from each other to prevent CDs from reacting through more than one site is reported. Using a "catch-and-release" process based on the Staudinger reaction, the utility of this concept to easily produce complex CD functionalization patterns in one pot and without any purification step is demonstrated.