在此,我们报道了使用 TEMPO 衍生的烷氧基胺进行光氧化还原亲核(放射性)氟化,这是一类底物,可通过多种容易获得的羧酸、卤化物、烯烃、醇、醛、硼试剂和 C-H 一步获得债券。这种温和且通用的单电子途径提供了放射性标记的脂肪族氟化物,由于反应性不足和竞争性消除,应用传统的亲核取代技术通常无法获得这些氟化物。该光氧化还原过程的自动化还通过用户友好且市售的光氧化还原流反应器和放射合成平台进行了演示,因此加快了获得高摩尔活性 ( A m ) 的标记脂肪族氟化物的速度,以进行临床(前)评估。
Investigation into an Unexpected Impurity: A Practical Approach to Process Development for the Addition of Grignard Reagents to Aldehydes Using Continuous Flow Synthesis
This work presents a case study of processdevelopment using continuousflow synthesis. In developing a process for manufacturing drug substances in batch reactors, we unexpectedly obtained a significant amount of a trimerized byproduct on addition of MeMgBr to an aldehyde. Consideration of a plausible generation mechanism for the byproduct indicated that it arose from a reaction between the starting