Xu Wen-Lei, Zhao Wei-Ming, Zhang Ru-Xia, Chen Jie, Zhou Ling
Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry & Materials Science, Northwest University Xi'an 710102 P. R. China
Chem Sci. 2021 Oct 30;12(44):14920-14926. doi: 10.1039/d1sc05161j. eCollection 2021 Nov 17.
The first chiral phosphoric acid (CPA) catalyzed cycloaddition-elimination cascade reaction of 2-naphthol- and phenol-derived enecarbamates with azonaphthalenes has been established, providing a highly atroposelective route to an array of axially chiral aryl-C3-benzoindoles in excellent yields with excellent enantioselectivities. The success of this strategy derives from the stepwise process involving CPA-catalyzed asymmetric formal [3 + 2] cycloaddition and subsequent central-to-axial chirality conversion by elimination of a carbamate. In addition, the practicality of this reaction had been verified by varieties of transformations towards functionalized atropisomers.
首次实现了手性磷酸（CPA）催化的2-萘酚和苯酚衍生的烯基氨基甲酸酯与氮杂萘的环加成-消除串联反应，为一系列轴手性芳基-C3-苯并吲哚提供了一条高对映选择性的合成路线，产率和对映选择性均优异。该策略的成功源于逐步过程，包括CPA催化的不对称形式[3 + 2]环加成以及随后通过消除氨基甲酸酯实现的中心到轴手性转化。此外，通过对官能化阻转异构体的各种转化验证了该反应的实用性。
