Enantioselective Oxidative Coupling of β-Ketocarbonyls and Anilines by Joint Chiral Primary Amine and Selenium Catalysis
作者:Wanting Chen、Yanni Wang、Xueling Mi、Sanzhong Luo
DOI:10.1021/acs.orglett.9b02636
日期:2019.10.18
An enantioselective primary amine-catalyzed total N-selective nitroso aldol reaction (N-NA) was achieved through the oxidation of primary aromatic amines to the corresponding nitrosoarenes catalyzed by selenium reagents and 30% H2O2. This protocol provides a facile and highly efficient access to α-hydroxyamino carbonyls bearing chiral quaternary centers under exceedingly mild and green reaction conditions
通过硒试剂和30%H 2 O 2催化伯芳族胺氧化为相应的亚硝基芳烃,可实现对映选择性伯胺催化的总N选择性亚硝基醛醇缩合反应(N -NA)。该方案可在极其温和和绿色的反应条件下,通过高度化学和对映体控制,轻松而高效地接近带有手性季中心的α-羟氨基羰基。
Reagent-controlled enantioselectivity switch for the asymmetric fluorination of β-ketocarbonyls by chiral primary amine catalysis
作者:Yang'en You、Long Zhang、Sanzhong Luo
DOI:10.1039/c6sc03109a
日期:——
enantioselectivity switch was uncovered in the asymmetric α-fluorination of β-ketocarbonyls by a chiral primary amine catalyst. By a simple swap of fluorination reagents, both enantiomers of the quaternary fluorination adducts could be obtained with good yields and high enantioselectivity. Mechanistic studies disclosed dual H-bonding and electrostatic stereocontrolling modes for the catalysis.
Chiral Primary Amine/Ketone Cooperative Catalysis for Asymmetric α-Hydroxylation with Hydrogen Peroxide
作者:Mao Cai、Kaini Xu、Yuze Li、Zongxiu Nie、Long Zhang、Sanzhong Luo
DOI:10.1021/jacs.0c11787
日期:2021.1.20
catalytic strategies, aminocatalysis and carbonyl catalysis do not coexist well, and, as such, a cooperative amine/carbonyl dual catalysis remains essentially unknown. Here we report a cooperative primary amine and ketone dual catalytic approach for the asymmetric α-hydroxylation of β-ketocarbonyls with H2O2. Besides participating in the typical enamine catalytic cycle, the chiral primary amine catalyst
Catalytic Asymmetric Mannich Reaction with N-Carbamoyl Imine Surrogates of Formaldehyde and Glyoxylate
作者:Yang'en You、Long Zhang、Linfeng Cui、Xueling Mi、Sanzhong Luo
DOI:10.1002/anie.201707005
日期:2017.10.23
N,O‐acetals (NOAcs) were developed as bench stable surrogates for N‐carbamoyl, (Boc, Cbz and Fmoc) formaldehyde and glyoxylate imines in asymmetric Mannich reactions. The NOAcs can be directly utilized in the chiral primary amine catalyzed Mannich reactions of both acyclic and cyclic β‐ketocarbonyls with high yields and excellent stereoselectivity. The current reaction offers a straightforward approach
Phosphine-Catalyzed Diastereo- and Enantioselective Michael Addition of β-Carbonyl Esters to β-Trifluoromethyl and β-Ester Enones: Enhanced Reactivity by Inorganic Base
A novel chiral biamide–phosphine multifunctional catalyst has been developed that mediates the asymmetric intermolecular Michael addition of β-carbonyl esters to β-trifluoromethyl enones and 3-aroyl acrylates in the presence of competing methyl acrylate and the inorganic base. This method provides a facile access to structurally diversetrifluoromethyl and quaternary stereogenic centers with excellent
已经开发出一种新型的手性联酰胺-膦多功能催化剂,该催化剂在竞争性丙烯酸甲酯和无机碱的存在下,将β-羰基酯的不对称分子间迈克尔加成反应成β-三氟甲基烯酮和3-芳基丙烯酸酯。此方法可轻松访问结构多样的三氟甲基和季立体异构中心,具有出色的对映选择性(高达99%ee)和良好的非对映选择性(高达13:1 dr)。无机碱(K 3 PO 4)的添加不会引起背景外消旋反应,并且通过用作助催化剂来增强反应性。