Wu Jun, Purushothaman Rajeshwaran, Kallert Felix, Homölle Simon L, Ackermann Lutz
Wöhler-Research Institute for Sustainable Chemistry, Georg-August-Universität Göttingen, Tammannstraße 2, Göttingen 37077, Germany.
ACS Catal. 2024 Jul 19;14(15):11532-11544. doi: 10.1021/acscatal.4c02322. eCollection 2024 Aug 2.
Glycosyl donor activation emerged as an enabling technology for anomeric functionalization, but aimed primarily at -glycosylation. In contrast, we herein disclose mechanistically distinct electrochemical glycosyl bromide donor activations via halogen-atom transfer and anomeric -glycosylation. The anomeric radical addition to alkenes led to -alkyl glycoside synthesis under precious metal-free reaction conditions from readily available glycosyl bromides. The robustness of our e-XAT strategy was further mirrored by -aryl and -acyl glycosides assembly through nickela-electrocatalysis. Our approach provides an orthogonal strategy for glycosyl donor activation with expedient scope, hence representing a general method for direct -glycosides assembly.
糖基供体活化成为一种用于异头官能化的使能技术，但主要针对β-糖基化。相比之下，我们在此公开了通过卤原子转移和异头β-糖基化实现的机理不同的电化学糖基溴供体活化。在无贵金属的反应条件下，从易得的糖基溴出发，异头自由基加成到烯烃上可实现α-烷基糖苷的合成。我们的电子卤原子转移（e-XAT）策略的稳健性还体现在通过镍电催化实现α-芳基和α-酰基糖苷的组装上。我们的方法为糖基供体活化提供了一种正交策略，适用范围广泛，因此代表了一种直接合成α-糖苷的通用方法。
