Catalytic Asymmetric 1,3‐Dipolar Cycloaddition of β‐Fluoroalkylated α,β‐Unsaturated 2‐Pyridylsulfones with Nitrones for Chiral Fluoroalkylated Isoxazolidines and γ‐Amino Alcohols
作者:Xing Yang、Feng Cheng、Ying‐Da Kou、Shuai Pang、Yong‐Cun Shen、Yi‐Yong Huang、Norio Shibata
DOI:10.1002/anie.201610605
日期:2017.2
across various aromatic and aliphatic nitrones in the presence of a chiral NiII/bis(oxazoline) catalyst. The process was tuned by 4 Å molecular sieves, chiral bis(oxazoline) ligands, reaction solvents, and temperature. A wide array of optically pure fluoroalkylated isoxazolidines were obtained, thus facilitating the asymmetric synthesis of an enantioenriched α‐trifluoromethylated γ‐amino alcohol in gram‐scale
在手性Ni II的存在下,2-吡啶基砜和氟烷基化的基团活化的烯烃在各种芳族和脂肪族硝基上进行了高效的非对映和对映选择性的1,3-偶极环加成反应/双(恶唑啉)催化剂。该过程通过4Å分子筛,手性双(恶唑啉)配体,反应溶剂和温度进行调节。获得了大量光学上纯的氟代烷基化的异恶唑烷,从而促进了对映体富集的对映体富集的克级α-三氟甲基化γ-氨基醇和1,3-氧杂恶嗪-2-酮的三氟甲基化衍生物的合成,具有潜在的药用价值。根据一种加合物的绝对构型和一些对照实验,建立了立体化学模型,以解释观察到的内选择性和对映选择性。