Article
Chemistry, Physical
Mariola Zielinska-Blajet, Joanna Najdek
Summary: An efficient approach to synthesizing chiral selenoureas derived from Cinchona alkaloid scaffolds was described in this study. These selenoureas were evaluated as bifunctional organocatalysts in asymmetric Michael addition reactions, with the best results achieved by those containing the 4-fluorophenyl group, showing enantioselectivities up to 96% ee. Additionally, the catalytic performance of thiourea and selenourea counterparts was compared.
Article
Chemistry, Organic
Francesca Franco, Sara Meninno, Jacob Overgaard, Sergio Rossi, Maurizio Benaglia, Alessandra Lattanzi
Summary: An enantioselective synthesis method for functionalized triflones with a quaternary stereocenter has been developed, utilizing the Michael reaction and nucleophilic acyl substitution. The study highlights the potential of the triflinate anion as a leaving group for stereocontrolled postfunctionalizations.
Review
Chemistry, Organic
Maciej Majdecki, Patryk Niedbala, Agata Tyszka-Gumkowska, Janusz Jurczak
Summary: This short review focuses on asymmetric phase-transfer reactions using hybrid ammonium Cinchona catalysts with hydrogen-bond donor groups. The emphasis is on the advantages of additional functional groups present in the catalyst structure.
SYNTHESIS-STUTTGART
(2021)
Article
Biochemistry & Molecular Biology
Mariola Zielinska-Blajet, Zaneta A. Mala, Rafal Kowalczyk
Summary: Novel chiral Cinchona-alkaloid based selenoureas were developed by varying the steric and electronic surroundings of the hydrogen-bonding motif, showing high efficiency in catalyzing Michael reactions and achieving chiral products with high enantioselectivity. The asymmetric Michael-hemiacetalization reaction of benzylidene pyruvate and dimedone, catalyzed by selenoureas, resulted in good yields and high enantioselectivity. The efficacy of the new hydrogen-bond donors was further confirmed in solvent-free reactions under ball mill conditions, supporting the sustainability of the devised catalytic protocol.
Article
Chemistry, Organic
Deniz Tozendemir, Cihangir Tanyeli
Summary: Cinchona alkaloid-derived organocatalysts have been widely utilized in asymmetric transformations, resulting in products with high enantiopurity. A bifunctional quinine-derived sulfonamide organocatalyst was developed for catalyzing the asymmetric sulfa-Michael reaction, achieving high enantioselectivity with low catalyst loading. The enriched sulfa-Michael addition products were successfully oxidized to obtain the corresponding sulfones.
BEILSTEIN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Abhisek Midya, Laxman Devidas Khalse, Prasanta Ghorai
Summary: An unprecedented enantioselective organocatalytic spirocyclization strategy was developed by in situ generation of aminoisobenzofulvenes and utilizing iminium-enamine catalysis for a reductive Michael/aldol-condensation/Michael addition cascade. This strategy showed remarkable success in the synthesis of all carbon quaternary spirocycles and demonstrated post-methodological manipulation of the products.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Multidisciplinary
Alessandra Lattanzi
Summary: The development of organocatalysis and the use of Michael addition reaction have greatly contributed to the synthesis of quaternary stereocenters and the preparation of functionalized building blocks. In this account, the authors highlight their achievements in accessing novel heterocycles with quaternary stereocenters, particularly focusing on the use of organocatalysis derived from Cinchona alkaloids. The enantioenriched heterocycles obtained were further manipulated to prepare useful compounds for downstream applications.
Article
Chemistry, Applied
Laura A. Bryant, Kenneth Shankland, Hannah E. Straker, Callum D. Johnston, Nicholas R. Lees, Alexander J. A. Cobb
Summary: The article describes a rare organocatalytic intramolecular cyclization of resorcinols with a high enantioselectivity using a specific organocatalyst. The obtained bicyclic resorcinols show excellent utility in the synthesis of cannabinoid-like compounds, and exhibit anticonvulsant activity.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Biochemistry & Molecular Biology
Patryk Niedbala, Maciej Majdecki, Piotr Grodek, Janusz Jurczak
Summary: This work describes the development of a highly optimized method for generating quaternary stereogenic centers in beta-keto esters. The method utilizes a phase-transfer alkylation reaction catalyzed by hybrid Cinchona catalysts, resulting in efficient generation of optically active products with excellent enantioselectivity using only 1 mol% catalyst.
Article
Chemistry, Organic
Mohammad Farhadur Rahman, Chouthor Yangyuayang, Ikuhide Fujisawa, Naoki Haraguchi, Shinichi Itsuno
Summary: The C5'-nitro-dihydroquinine (Q1), derived from dihydroquinine (HQ), exhibited superior catalytic activity and asymmetric induction in an asymmetric Michael reaction.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Review
Chemistry, Multidisciplinary
Xin Huang, Wei Zhang
Summary: Organocatalysis offers unique activation modes, mild reaction conditions, and good catalyst adaptability, making it more efficient with the integration of green techniques. This article focuses on recyclable cinchona alkaloid-catalyzed reactions in the asymmetric synthesis of functionalized compounds of biological interest.
CHEMICAL COMMUNICATIONS
(2021)
Article
Chemistry, Applied
Irma Garcia-Monzon, Jorge Borges-Gonzalez, Tomas Martin
Summary: The heterogenization of homogeneous catalysts onto a solid support is a crucial step towards sustainable chemistry. In this study, we developed a series of polymer-supported tetrahydropyran-based hybrid dipeptides as active catalysts for the enantioselective Michael addition of aldehydes to beta-nitrostyrenes. The optimal anchor position and orientation between the catalyst and solid support, as well as the linker length, were carefully designed to enhance the catalytic efficiency. These supported catalysts exhibited high yields and enantiomeric excesses, and detailed deactivation studies provided important insights for prolonging their useful life.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
Article
Chemistry, Multidisciplinary
Xiu-Ning Hu, Dong-Ping Wu, Ye-Peng Xu, Pei-Qiang Huang
Summary: The first organocatalytic asymmetric synthesis of an advanced intermediate of (+)-sarain A was achieved by combining organocatalytic asymmetric Michael addition reaction and a nitrogen-to-carbon chirality transfer. This method allows for the construction of three chiral centers and chemoselective reduction of a key lactam intermediate, providing a tricyclic intermediate with all necessary functionalities for further elaboration into (+)-sarain A.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Organic
Naoki Sakai, Kyohei Kawashima, Masashi Kajitani, Seiji Mori, Takeshi Oriyama
Summary: This study reported the first asymmetric Michael addition of alpha-aminomaleimides as Michael donors to beta-nitrostyrenes using an organocatalyst derived from a Cinchona alkaloid. Density functional theory investigations were crucial for improving the enantioselectivity of the adduct.
Article
Chemistry, Applied
Andrea Guerrero-Corella, Miguel A. Valle-Amores, Alberto Fraile, Jose Aleman
Summary: An asymmetric organocatalytic aza-Michael addition reaction of ketimines to nitroolefins is described, utilizing 2-hydroxybenzophenone imine to improve the enantioselective addition of N-centered nucleophiles to nitroalkenes. The versatility of the process is demonstrated under both batch and flow conditions, resulting in the synthesis of a wide variety of nitroamine derivatives with excellent yields and enantioselectivities. Additionally, this methodology was successfully applied to the formal synthesis of VNI, a drug-like scaffold for the treatment of Chagas disease.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Inorganic & Nuclear
Nasarul Islam, Swapandeep Singh Chimni
JOURNAL OF COORDINATION CHEMISTRY
(2017)
Article
Chemistry, Organic
Karandeep Singh, Bhanwar Kumar Malviya, Tapta Kanchan Roy, Venus Singh Mithu, Vimal K. Bhardwaj, Ved Prakash Verma, Swapandeep Singh Chimni, Siddharth Sharma
JOURNAL OF ORGANIC CHEMISTRY
(2018)
Article
Chemistry, Organic
Anita Kumari, Jasneet Kaur, Vimal K. Bhardwaj, Swapandeep Singh Chimni
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2018)
Article
Chemistry, Organic
Vivek Sharma, Jasneet Kaur, Swapandeep S. Chimni
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2018)
Review
Chemistry, Organic
Jasneet Kaur, Swapandeep Singh Chimni
ORGANIC & BIOMOLECULAR CHEMISTRY
(2018)
Article
Chemistry, Multidisciplinary
Vivek Sharma, Vimal K. Bhardwaj, Swapandeep S. Chimni
Article
Chemistry, Organic
Vivek Sharma, Anmolpreet Kaur, Subash Chandra Sahoo, Swapandeep Singh Chimni
ORGANIC & BIOMOLECULAR CHEMISTRY
(2018)
Article
Chemistry, Organic
Karandeep Singh, Bhanwar Kumar Malviya, Pradeep K. Jaiswal, Ved Prakash Verma, Swapandeep Singh Chimni, Siddharth Sharma
Article
Chemistry, Organic
Banni Preet Kaur, Vivek Sharma, Subash Chandra Sahoo, Swapandeep Singh Chimni
Summary: Enantiopure bis-heterocyclic molecules containing pyrazole and isoxazole were synthesized via a low-catalyst loading Michael addition reaction under mild conditions with high yields and enantiomeric excess. These derivatives can be further transformed into potentially bio-active molecules with significant applications. The synthesis of these bis-heterocyclic molecules can be efficiently carried out in one pot without any loss of enantiopurity, adding to their significance.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Review
Chemistry, Multidisciplinary
Banni Preet Kaur, Jasneet Kaur, Swapandeep Singh Chimni
Summary: Arenesulfonyl indoles, with a good leaving group, serve as effective precursors for vinylogous imine intermediates generated in situ under basic conditions. These intermediates readily react with other nucleophilic reagents to yield C-3 substituted indole derivatives. The success of this substrate in organic synthesis is attributed to the stability of arylsulfonyl-containing substrates, mild reaction conditions, and the wide variety of nucleophiles involved.
Article
Chemistry, Medicinal
Naveen Kumar, Akshay Kumar, Subash Chandra Sahoo, Swapandeep Singh Chimni
Review
Chemistry, Organic
Jasneet Kaur, Banni Preet Kaur, Swapandeep Singh Chimni
ORGANIC & BIOMOLECULAR CHEMISTRY
(2020)
Article
Chemistry, Organic
Arun Sharma, Vivek Sharma, Swapandeep Singh Chimni
ORGANIC & BIOMOLECULAR CHEMISTRY
(2019)
Review
Chemistry, Multidisciplinary
Jasneet Kaur, Pankaj Chauhan, Sarbjit Singh, Swapandeep Singh Chimni
Article
Chemistry, Applied
Jasneet Kaur, Anita Kumari, Vimal K. Bhardwaj, Swapandeep Singh Chimni
ADVANCED SYNTHESIS & CATALYSIS
(2017)
