Department of Chemistry and Biochemistry, University of Arizona, 1306 East University Boulevard, Tucson, Arizona 85721, USA.
J Org Chem. 2012 Feb 3;77(3):1289-300. doi: 10.1021/jo201753q. Epub 2012 Jan 23.
Multifunctionalized amino acids, especially amino acids with unsaturation, are important, demanding building blocks in peptide chemistry. Here we present a summary of our most recent study using the thio-Claisen rearrangement for the synthesis of anti-β-functionalized γ,δ-unsaturated amino acids. Investigations on scope, limitations, chemoselectivities and stereoselectivities regarding an FeBr(3)-catalyzed allylation strategy and a thio-enolate dianion formation strategy for asymmetric thio-Claisen rearrangement are documented. An explanation of the chirality crossover observed between the Eschenmoser-Claisen rearrangement and the thio-Claisen rearrangement is proposed. Novel optically active N(α)-protected amino acids with biologically interesting functional groups were prepared for the first time.
多功能化氨基酸，尤其是具有不饱和键的氨基酸，是肽化学中重要且要求苛刻的构建模块。在这里，我们总结了最近使用硫-Claisen 重排合成反式-β-功能化γ,δ-不饱和氨基酸的研究。我们记录了关于 FeBr(3)催化的烯丙基化策略和硫代烯醇二阴离子形成策略的不对称硫-Claisen 重排的范围、限制、化学选择性和立体选择性的研究。我们提出了在 Eschenmoser-Claisen 重排和硫-Claisen 重排之间观察到的手性交叉的解释。首次制备了具有生物活性官能团的新型手性保护的 N(α)-氨基酸。
