Article
Chemistry, Organic
Laxman Devidas Khalse, Prasanta Ghorai
Summary: An efficient cascade protocol for the stereoselective synthesis of borylated carbocycles has been developed. This approach involves copper-catalyzed borylative Michael/Michael cyclization and allows the preparation of 24 new boronic ester substituted indanes, cyclohexanes, and cyclopentanes in good yields with excellent diastereoselectivities and functional group tolerance. The synthetic transformation of carbacyclic boronates was also successfully demonstrated, and gram-scale synthesis was carried out effectively.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Won Jun Jang, Jeongkyu Woo, Jaesook Yun
Summary: The study reported a method to synthesize enantioenriched alkylboron compounds through conjugate addition, which are influenced by two contiguous carbon stereogenic centers, with high yield and enantioselectivity.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Hu Tian, Hong-Ming Zhang, Liang Yin
Summary: In this article, a copper(I)-catalyzed asymmetric conjugate addition/protonation with selenols and alpha-substituted alpha,beta-unsaturated thioamides is described, which produces a series of chiral selenides with high to excellent enantioselectivity. The reaction shows a broad substrate scope for both selenols and alpha-substituted alpha,beta-unsaturated thioamides. The catalytic system is also successfully used for asymmetric selenation of beta-substituted alpha,beta-unsaturated thioamides. A [Cu-(R,R-P)-TANIAPHOS]-SePh species is identified by Se-77 NMR spectra, with a chemical shift at delta 462 ppm. Furthermore, a {[Cu-(R)-TOL-BINAP]-SePh}(2) species is characterized by X-ray analysis, confirming the formation of Cu-Se bond in the reaction. Finally, the straightforward transformations of the thioamide group to amine and thioester are demonstrated.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Applied
Deyuan Meng, Jing He, Woojin Yoon, Hoseop Yun, Jung Tae Han, Jaesook Yun
Summary: In this study, the catalytic 1,6-addition of chiral alkyl copper nucleophiles generated from borylalkenes and a copper-hydride catalyst was successfully conducted under mild conditions. The controlled chemo- and stereoselectivity played a crucial role in the reductive coupling process, resulting in efficient synthesis of asymmetric 1,6-adducts of p-quinone methides through multicomponent and catalytic tandem reactions.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Brian S. Daniels, Xintong Hou, Stephanie A. Corio, Lindsey M. Weissman, Vy M. Dong, Jennifer S. Hirschi, Shaozhen Nie
Summary: A copper catalyst is reported for the addition of phosphines to cyclopropenes at ambient temperature. Various cyclopropylphosphines with different steric and electronic properties can now be synthesized in high yields and enantioselectivities. Through a combined experimental and theoretical study, the mechanism is proposed to involve insertion of a Cu-I-phosphido into a carbon-carbon double bond.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Junwen Wang, Jun Li, Yan Wang, Sisi He, Hengzhi You, Fen -Er Chen
Summary: In this study, a polymer-supported chiral heterogeneous copper catalyst was reported, which demonstrated high reactivity and enantioselectivity in asymmetric conjugate addition reactions.
Article
Chemistry, Multidisciplinary
Yu-Chao Wang, Zhao-Xin Xiao, Miao Wang, Shao-Qian Yang, Jin-Biao Liu, Zhi-Tao He
Summary: This study presents modular protocols for 1,5-conjugate addition reactions via palladium hydride catalysis, which has been considered unfeasible. The results show that the 1,5-conjugate addition products can be conveniently transformed into various privileged enantioenriched motifs, indicating the potential applications of this method in synthesis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Ken-Loon Choo, Bijan Mirabi, Karl Z. Demmans, Mark Lautens
Summary: Enantioenriched spiro-oxiranes with three contiguous stereocenters were synthesized using a rhodium-catalyzed cascade reaction, enabling the formation of a spirocyclic framework in a single step. Both sp(2)- and sp-hybridized carbon nucleophiles were found to be efficient initiators, yielding products with different functional groups. Derivatization studies demonstrated the synthetic versatility of the products' epoxide and alkyne moieties. DFT calculations were employed to explain spectroscopic discrepancies between solution- and solid-state structures of the products.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Multidisciplinary
Soshi Nishino, Yuji Nishii, Koji Hirano
Summary: A copper-catalyzed reaction has been developed for the regio- and diastereoselective borylamination of alpha,beta-unsaturated esters with B(2)pin(2) and hydroxylamines. The reaction delivers acyclic beta-boryl-alpha-amino acid derivatives with high anti-diastereoselectivity, which is difficult to achieve using established methods. Furthermore, the use of a chiral phosphoramidite ligand allows for the enantioselective synthesis of optically active beta-borylated alpha-amino acids. The resulting products can be further transformed into beta-functionalized alpha-amino acids, which are of great interest in medicinal chemistry.
Article
Chemistry, Applied
Brigita Mudrakova, Peter Kisszekelyi, Denisa Vargova, Dorota Zakiewicz, Radovan Sebesta
Summary: This paper presents a highly enantio- and diastereoselective tandem transformation method, using Cu-catalyzed conjugate addition of Grignard reagents to heterocyclic Michael acceptors, followed by one-pot trapping of in situ formed enolates with stabilized carbocations or their equivalents. This method allows the installation of structurally attractive substituents on heterocyclic compounds.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Changli He, Xiaoxue Tang, Xin He, Yuqiao Zhou, Xiaohua Liu, Xiaoming Feng
Summary: Reversal of regioselectivity in the catalytic asymmetric conjugate additions of 3-substituted oxindoles to beta-nitroenones or beta-nitroacrylates was achieved with chiral scandium catalysts. Functionalized 3,3-disubstituted oxindoles, including terminal and internal vinyl groups, were constructed in excellent yields and ee values.
CHINESE CHEMICAL LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Ming Cui, Zhi-Yuan Zhao, Martin Oestreich
Summary: Chiral bis(phosphine) monooxides derived from C-2-symmetric bis(phosphines) have been found to exhibit superior enantioselection in copper-catalyzed conjugate borylation and 1,6-addition reactions. Specifically, (R,R)-Bozphos ligand shows significantly higher enantiomeric excesses and chemical yields compared to parent (R,R)-Me-Duphos ligand.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Applied
Gianluca Casotti, Vincenzo Rositano, Anna Iuliano
Summary: Stabilised arylzinc iodide prepared by direct insertion of zinc into aryl iodides, were successfully applied as nucleophiles in the Hayashi Rh-catalysed enantioselective conjugate addition to enones, with high yields and 99% ee of the addition product. The general applicability of the protocol was confirmed by using different arylzinc iodides and enones, as well as organometallic reagents with both halogen and electrophilic groups.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Multidisciplinary
Zhi-Yuan Zhao, Ming Cui, Elisabeth Irran, Martin Oestreich
Summary: This study successfully achieved highly enantioselective silylation of 3-substituted 2H-azirines using a copper-catalyzed reaction with a silyl boronic ester as a latent silicon nucleophile. The resulting C-silylated, unprotected (N-H) aziridines were obtained in high yields and with excellent enantioselectivities, and they can be further converted into valuable compounds without significant loss of enantiomeric excess.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Wenjun Luo, Li-Ming Zhang, Zhan-Ming Zhang, Junliang Zhang
Summary: A novel family of PNP ligands (W-Phos) was designed and applied in the copper-catalyzed asymmetric addition of linear Grignard reagents to aryl alkyl ketones. This method allows for the facile synthesis of versatile chiral tertiary alcohols with high yields and excellent enantioselectivities. It also has the potential for the synthesis and modification of various densely functionalized medicinally relevant molecules.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)