Asymmetric [3 + 3] Annulation to Construct Trifluoromethylated Pyrazolo[3,4-<i>b</i>]pyridin-6-ones via Chiral Phosphoric Acid and MgSO<sub>4</sub> Synergistic Catalysis
作者:Alemayehu Gashaw Woldegiorgis、Zhao Han、Xufeng Lin
DOI:10.1021/acs.orglett.2c01513
日期:2022.6.10
and diastereoselective synthesis of pyrazolo[3,4-b]pyridin-6-ones bearing a −CF3 unit via synergistic chiral phosphoric acid and MgSO4 catalysis. This [3 + 3] annulation protocol allows the formation of trifluoromethylated pyrazolo[3,4-b]pyridin-6-ones with two adjacent tertiary stereocenters in moderate to high yields (up to 90%), enantioselectivities (up to 97% ee), and diastereoselectivities (up
我们开发了一种新颖的不对称 Friedel-Crafts 烷基化/转酰胺基串联反应,用于通过协同手性磷酸和 MgSO 4催化合成带有 -CF 3单元的吡唑并[3,4- b ]吡啶-6-酮的对映选择性和非对映选择性。这种 [3 + 3] 环化方案允许以中等至高产率(高达 90%)、对映选择性(高达 97% ee ) 和非对映选择性(高达 >20:1 dr)。