National Engineering Research Center of Chiral Drugs, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu, 610041, China.
Institute for Advanced Study, Chengdu University, Chengdu, 610106, China.
Org Biomol Chem. 2020 Mar 11;18(10):1886-1891. doi: 10.1039/c9ob02733e.
Two new types of cyclic pyridinium ylides were designed and further used in reactions with azoalkenes to access structurally diverse spirocyclic compounds. A range of spiropyrazoline oxindoles could be smoothly obtained in up to 99% yield via a [4 + 1] annulation process with oxindole 3-pyridinium ylides as C1 synthons. Similarly, a series of spiropyrazoline indanones could be prepared with indanone 2-pyridinium ylides as C1 synthons. This work represents the first example of cyclic pyridinium ylides as C1 synthons for the efficient construction of spirocyclic compounds.
两种新型的环状吡啶𬭩叶立德被设计出来，并进一步用于与偶氮烯烃的反应中，以获得结构多样的螺环化合物。通过[4+1]环加成反应，以吲哚啉-3-吡啶𬭩叶立德作为 C1 合成子，可以顺利地获得高达 99%收率的螺吡唑啉氧吲哚；类似地，以茚酮-2-吡啶𬭩叶立德作为 C1 合成子，可以制备一系列螺吡唑啉茚酮。这项工作代表了环状吡啶𬭩叶立德作为 C1 合成子用于高效构建螺环化合物的首例。
