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, 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.
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)
Review
Chemistry, Applied
Sushovan Paladhi, Jin Hyun Park, Barnali Jana, Han Yong Bae, Choong Eui Song
Summary: This review summarizes recent advances in the construction of all-carbon quaternary or hetero-carbon quaternary stereocenters via metal-catalyzed and organocatalyzed asymmetric conjugate addition to β,β-disubstituted nitroalkenes, focusing on the scope, applications, and mechanisms of these reactions.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
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, Multidisciplinary
Masanori Yoshida
Summary: This article describes recent developments in asymmetric synthesis of a quaternary carbon stereogenic center using organocatalysis with a primary amino acid and its salt as a catalyst. The three chapters cover conjugate addition to nitroalkenes and vinyl ketones, nucleophilic addition to pi-allyl palladium complexes, and nucleophilic substitution reactions with allyl and propargyl halides. These methods have successfully achieved asymmetric alpha-allylation of alpha-branched aldehydes and ketones, giving gamma-nitroaldehydes, ketoaldehydes, alpha-allylated aldehydes, and alpha-allylated beta-ketoesters with a quaternary carbon stereogenic center in good yields and high enantioselectivities.
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, Applied
Claire Segovia, Jeremy Godemert, Jean-Francois Briere, Vincent Levacher, Sylvain Oudeyer
Summary: An organocatalyzed one-pot sequential deracemization of aromatic ketones with a stereogenic center at the alpha-position was achieved through an acid-base strategy, in which enantioselective protonation reaction played a key role. This protocol provides enantioenriched ketones with up to 89% ee without isolating sensitive intermediates like silyl enolates. Water was found to be crucial in this process. This one-pot sequence serves as a valuable extension to previously reported chemically driven red-ox protocols, expanding the range of molecules eligible for deracemization.
ADVANCED SYNTHESIS & CATALYSIS
(2022)
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
Chemistry, Organic
Yiqun Zeng, Chao Fei, Xiao Zhou, Jisheng Luo, Li Deng
Summary: A newly developed betaine catalyst was used for an asymmetric isomerization of beta,gamma-unsaturated butenolides at a lower loading (0.2-2 mol%) compared to available methods (0.5-2.0 mol%).
Article
Chemistry, Organic
Daiki Ishii, Shin-ichi Hirashima, Kosuke Nakashima, Hiroshi Akutsu, Takaaki Sakai, Yasuyuki Matsushima, Masahiro Kawada, Tsuyoshi Miura
Summary: A new organocatalyst efficiently promotes the asymmetric direct vinylogous conjugate additions of alpha-angelica lactones to benzoyl acrylonitrile derivatives, resulting in products with excellent enantioselectivities. The chiral gamma,gamma-disubstituted gamma-butenolides obtained can be readily transformed to valuable synthetic intermediates.
Article
Chemistry, Applied
Marta Romaniszyn, Katarzyna Gronowska, Lukasz Albrecht
Summary: An organocatalytic 1,6-addition using 4-(alk-1-en-1-yl)-3-cyanocoumarins as acceptors has been developed, enabling the synthesis of hybrid molecules bearing two biologically relevant units with good site-selectivity and efficiency through appropriate substrate design and the application of a quinine-derived catalyst.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
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, Organic
Shu-Mei Yang, Ganapuram Madhusudhan Reddy, Meng-Hsien Liu, Tzu-Ping Wang, Jhen-Kuei Yu, Wenwei Lin
JOURNAL OF ORGANIC CHEMISTRY
(2017)
Article
Chemistry, Organic
Shu-Mei Yang, Yi-Ling Tsai, Ganapuram Madhusudhan Reddy, Lennart Mohlmann, Wenwei Lin
JOURNAL OF ORGANIC CHEMISTRY
(2017)
Article
Chemistry, Multidisciplinary
Shu-Mei Yang, Chein-Yi Wang, Chun-Kai Lin, Praneeth Karanam, Ganapuram Madhusudhan Reddy, Yi-Ling Tsai, Wenwei Lin
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2018)
Article
Chemistry, Organic
Praneeth Karanam, Ganapuram Madhusudhan Reddy, Srinivasa Rao Koppolu, Wenwei Lin
TETRAHEDRON LETTERS
(2018)
Article
Chemistry, Multidisciplinary
Jhen-Kuei Yu, Han-Wei Chien, Yi-Jung Lin, Praneeth Karanam, Yu-Heng Chen, Wenwei Lin
CHEMICAL COMMUNICATIONS
(2018)
Article
Chemistry, Applied
Sandip Sambhaji Vagh, Praneeth Karanam, Cheng-Chieh Liao, Ting-Han Lin, Yan-Cheng Liou, Athukuri Edukondalu, Yi-Ru Chen, Wenwei Lin
ADVANCED SYNTHESIS & CATALYSIS
(2020)
Article
Chemistry, Applied
Min Wang, Ping-Yao Tseng, Woei-Jye Chi, Sundaram Suresh, Athukuri Edukondalu, Yi-Ru Chen, Wenwei Lin
ADVANCED SYNTHESIS & CATALYSIS
(2020)
Article
Chemistry, Organic
Pankaj Khairnar, Chi-Yi Wu, Yi-Fang Lin, Athukuri Edukondalu, Yi-Ru Chen, Wenwei Lin
Article
Chemistry, Organic
Pankaj Khairnar, Yin-Hsiang Su, Yung-Chang Chen, Athukuri Edukondalu, Yi-Ru Chen, Wenwei Lin
Article
Cell Biology
Ching-Chia Huang, Kuo-Hsuan Chang, Ya-Jen Chiu, Yi-Ru Chen, Tsai-Hui Lung, Hsiu Mei Hsieh-Li, Ming-Tsan Su, Ying-Chieh Sun, Chiung-Mei Chen, Wenwei Lin, Guey-Jen Lee-Chen
Summary: Alzheimer's disease is characterized by progressive memory and cognitive impairments due to the aggregation of misfolded amyloid beta. Novel synthetic coumarin derivatives ZN014 and ZN015 show potential as therapeutic candidates for AD by reducing A beta neurotoxicity through pleiotropic mechanisms and activating TRKB-mediated signaling pathways.
Article
Chemistry, Applied
Tsai-Hui Lung, Yi-Ru Chen, Chen-Ling Chang, Wey-Chyng Jeng, Pei-Shan Wu, Sandip Sambhaji Vagh, Gangababu Marri, Yi-Fang Lin, Wenwei Lin
Summary: A catalyst-controlled diversity-oriented synthesis of spirohydroquinoline-indandiones and 3-methylenehydroquinoline-indandiones was reported using ortho-sulfonamidophenyl-substituted para-quinone methides and allylidene-indandiones. Organobases such as DMAP or TMG were utilized to selectively control the reaction pathway, resulting in products with yields of 40-99% and excellent diastereoselectivities. Mechanistic studies revealed that spirohydroquinoline-indandione was the kinetic product, which underwent an unusual base-initiated 1,3-nitrogen rearrangement process to afford 3-methylenehydroquinoline-indandione in the presence of TMG.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
Yi-Ru Chen, Madhusudhan Reddy Ganapuram, Kai-Hong Hsieh, Kai-Han Chen, Praneeth Karanam, Sandip Sambhaji Vagh, Yan-Cheng Liou, Wenwei Lin
CHEMICAL COMMUNICATIONS
(2018)
Article
Chemistry, Multidisciplinary
Shu-Mei Yang, Ganapuram Madhusudhan Reddy, Tzu-Ping Wang, Yu-Sheng Yeh, Min Wang, Wenwei Lin
CHEMICAL COMMUNICATIONS
(2017)
Article
Chemistry, Multidisciplinary
Yi-Ru Chen, Ganapuram Madhusudhan Reddy, Shao-Hao Hong, Ying-Zheng Wang, Jhen-Kuei Yu, Wenwei Lin
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2017)
