Direct Asymmetric α‐Selective Mannich Reaction of β,γ‐Unsaturated Ketones with Cyclic α‐Imino Ester: Divergent Synthesis of Cyclocanaline and Tetrahydro Pyridazinone Derivatives
作者:Yu‐Huan Geng、Yuan‐Zhao Hua、Shi‐Kun Jia、Min‐Can Wang
DOI:10.1002/chem.202100284
日期:2021.3.17
The first regio‐, diastereo‐, and enantioselective direct Mannich reaction of β,γ,‐unsaturated ketones with benzoxazinone cyclic imines was enabled by Lewis acid/Brønsted base cooperative catalysis. The dinuclearzinc complex catalyzed the reaction of a broad range of β,γ‐unsaturated ketones to proceed at the α‐site exclusively, leading to corresponding adducts with two consecutive tertiary carbon
路易斯酸/布朗斯台德碱协同催化作用使β,γ-不饱和酮与苯并恶嗪酮环状亚胺进行了第一个区域,非对映和对映选择性的直接曼尼希反应。双核锌络合物催化广泛的β,γ-不饱和酮反应仅在α位进行,从而导致相应的加合物具有两个连续的叔碳立体中心,其非对映异构体比例高达> 20:1,并且通常具有对映选择性在90–99%ee范围内。这些产物被用作一般中间体,用于合成多取代的环茶碱,四氢哒嗪酮和4 H-呋喃[2,3- b ] [1,4]苯并恶嗪衍生物。
Asymmetric alkenylation reaction of benzoxazinones with diarylethylenes catalyzed by B(C6F5)3/chiral phosphoric acid
作者:Zhen Liu、Zhi-Yuan Ren、Chen Yang、Xiangyi Shao、Li Chen、Xin Li
DOI:10.1016/j.cclet.2023.108939
日期:2024.5
Catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules, but the asymmetric alkenylation of simplealkenes catalyzed by metal-free catalysts remains an elusive challenge. Herein, we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(CF)/chiral phosphoric acid catalyst. A broad of benzoxazinones and diarylethylenes
B(C6F5)3/Chiral Phosphoric Acid Catalyzed Asymmetric Aza-Diels–Alder Reaction of Imines and Unactivated Dienes
作者:Zhen Liu、Qing-Chun Qian、Li-Ming Chen、Xin Li
DOI:10.1021/acs.orglett.4c00874
日期:2024.4.19
Herein, we report an asymmetric aza-Diels–Alderreaction of quinoxalinones or benzoxazinones with unactivated dienes by utilizing a B(C6F5)3/chiral phosphoric acid catalyst to construct chiral six-membered N-heterocycles. Various quinoxalinones or benzoxazinones with electron-withdrawing and electron-donating groups and unactivated dienes were tolerated (up to 99% yield and 99% ee) in the methodology