Organocatalytic stereoselective conjugate addition of 3-substituted oxindoles with in situ generated ortho-quinone methides
作者:Weihong Liang、Wenhao Yin、Tingzhong Wang、Fayang G. Qiu、Junling Zhao
DOI:10.1016/j.tetlet.2018.03.069
日期:2018.5
A novel method for the stereoselectiveconjugateaddition of 3-substituted oxindoles to in situ generated o-QMs was described. This process was catalyzed efficiently by a cinchonidine-derived squaramide catalyst in oil-water phase, furnishing the corresponding 3,3-disubsituted oxindole derivatives in moderate to high yields (up to 98%) with high stereoselectivities (up to 95% ee, 15.4:1 dr). The utility
A catalytic asymmetric allylic alkylation reaction of 3‐aryloxindoles was accomplished via a dual catalysis merging palladium catalysis and asymmetric H‐bonding catalysis for the first time. Using this approach, allylated oxindoles bearing chiral all‐carbon quaternary centers were produced in high yields with good enantioselectivities (up to 92 % yield and 96:4 er).
Catalytic Asymmetric Synthesis of 3,3′-Diaryloxindoles as Triarylmethanes with a Chiral All-Carbon Quaternary Center: Phase-Transfer-Catalyzed S<sub>N</sub>Ar Reaction
Catalyticasymmetric synthesis of unsymmetrical triarylmethanes with a chiral all‐carbon quaternarycenter was achieved by using a chiral bifunctionalquaternary phosphonium bromide catalyst in the SNAr reaction of 3‐aryloxindoles under phase‐transfer conditions. The presence of a urea moiety in the chiral phase‐transfer catalyst was important for obtaining high enantioselectivity in this reaction
在相转移条件下,通过手性双官能季铵溴化甲烷催化剂在3-芳基氧吲哚的S N Ar反应中使用手性双碳四级溴化catalyst催化剂,实现了具有手性全碳季中心的不对称三芳基甲烷的催化不对称合成。手性相转移催化剂中尿素部分的存在对于在该反应中获得高对映选择性很重要。
Bifunctional thiourea-modified polymers of intrinsic microporosity for enantioselective α-amination of 3-aryl-2-oxindoles in batch and flow conditions
作者:Laura Martín、Alicia Maestro、José M. Andrés、Rafael Pedrosa
DOI:10.1039/d0ob01373k
日期:——
Two novel polymers of intrinsic microporosity decorated with chiral thioureas have been used as recoverable organocatalysts in enantioselectiveα-amination of 3-aryl-substituted oxindoles, creating a quaternary stereocenter. Both catalysts were able to promote the reaction in excellent yields and good enantioselection. Catalyst II, with a pyridyl nucleus, was used in recycling experiments maintaining
Nickel(II)-Catalyzed Asymmetric Michael Addition of Oxindoles with Modified N,N,O-Tridentate Chiral Phenanthroline Ligands
作者:Yuki Naganawa、Hisao Nishiyama、Hiroki Abe
DOI:10.1055/s-0035-1561630
日期:——
Nickel(II)-catalyzed enantioselective Michael addition of N-Boc-oxindole derivatives with methyl vinyl ketone was demonstrated to give the corresponding adducts having chiral all-carbon quaternary centers with up to 87% ee in the presence of axially chiral N,N,O-tridentate phenanthroline ligand.
在轴向手性 N,N 存在下,镍 (II) 催化的 N-Boc-羟吲哚衍生物与甲基乙烯基酮的对映选择性迈克尔加成得到相应的加合物,其具有高达 87% 的 ee 手性全碳季中心, O-三齿菲咯啉配体。