Article
Chemistry, Multidisciplinary
Michael J. Tilby, Damien F. Dewez, Adrian Hall, Carolina Martinez Lamenca, Michael C. Willis
Summary: In this study, the absolute configuration of sulfur-stereogenic aza-sulfur derivatives was determined using a unique feature of sulfonimidamides. Enantioselective alkylation was achieved by generating prochiral ions from sulfonimidamides with the help of a bis-quaternized phase-transfer catalyst. This demonstrates the potential of using configurationally labile aza-sulfur species in asymmetric catalysis.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Organic
Fengbiao Luo, Hao Dong, Weiwu Ren, Yang Wang
Summary: In this study, the first catalytic asymmetric cycloannulation of ortho-aminophenyl p-QMs was developed for the construction of tetrahydroquinolines containing three contiguous stereogenic centers. The reaction exhibited excellent functional group tolerance and high enantioselectivity, resulting in excellent yields and exclusive diastereoselectivities.
Article
Chemistry, Organic
Ji-Wei Ren, Zhen-Zhen Xie, Lan Zheng, Zhi-Peng Ye, Zhi-Xiong Deng, Qing-Lan Zhao, Jun-An Xiao, Kai Chen, Hao-Yue Xiang, Xiao-Qing Chen, Hua Yang
Summary: In this work, an organocatalytic enantioselective ring-reorganization domino sequence was established for the synthesis of pyrrolo[3,4-c]quinolinones with multiple chiral centers. The reaction showed high yields, excellent diastereoselectivities, and high enantioselectivities.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Organic
Ramesh Samikannu, Sankaranarayanan Sethuraman, Nagaraja Akula, Vignesh Radhakrishnan, Srinivasarao Kamisetti, Shabana Banu, Muthalagu Vetrichelvan, Anuradha Gupta, Jianqing Li, Richard Rampulla, Arvind Mathur
Summary: A facile intramolecular cyclization of 3-hydroxy-3-(2-((3-methoxybenzyl)oxy)phenyl)indolin-2-one derivatives for the synthesis of spirooxindoles fused with dibenzoxepine moieties is described. The success of this reaction is highly dependent on solvent choice and the electronic nature of the aromatic ring. Various dibenzoxepine-fused spirooxindoles were successfully synthesized in up to 98% yield, providing libraries of structurally diverse and medicinally important small molecules for the search for new bioactive compounds.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2021)
Article
Chemistry, Organic
Rongqing Guan, He Zhao, Min Zhang
Summary: In this study, we have presented a novel annulation reaction for the synthesis of fused tetrahydroquinolines. By utilizing ruthenium catalyst, quinolinium salts can be reacted with indoles and paraformaldehyde to construct a wide range of fused tetrahydroquinolines with syn-diastereoselectivity. The reaction shows mild reaction conditions, excellent substrate and functional group compatibility, readily available feedstocks, and operational simplicity.
Article
Chemistry, Organic
Andrea Vopalenska, Vojtech Docekal, Simona Petrzelova, Ivana Cisarova, Jan Vesely
Summary: The present study reports an asymmetric organocascade reaction that efficiently catalyzes the reaction between oxindole-derived alkenes and 3-bromo-1-nitropropane using a bifunctional catalyst. The reaction produces spirooxindole-fused cyclopentanes in moderate-to-good isolated yields (15-69%) with excellent stereochemical outcomes. The synthetic utility of the protocol is demonstrated through additional transformations of the resulting spirooxindole compounds.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Jixin Pian, Qingqing Chen, Yujiao Luo, Zhifei Zhao, Jichang Liu, Lin He, Shi-Wu Li
Summary: An enantioselective cyclopropanation reaction of sulfoxonium ylides with beta,gamma-unsaturated ketoesters catalyzed by a chiral rhodium catalyst has been achieved, leading to the synthesis of various optically pure cyclopropanes.
Article
Chemistry, Organic
Chandrakanta Parida, Buddhadeb Mondal, Animesh Ghosh, Subhas Chandra Pan
Summary: A novel organocatalytic asymmetric synthesis method for spirooxindole embedded oxazolidines has been developed using a specific catalyst, resulting in good diastereoselectivity and high enantioselectivity of the products.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Suman Sar, Prasanta Ghorai
Summary: In this study, we report a highly selective P(NMe2)3 mediated intramolecular deoxygenation reaction which exhibits excellent substrate adaptability. This methodology provides a convenient access to valuable 6,5,3-fused scaffolds with an all-carbon quaternary stereocenter via Kukhtin-Ramirez (K-R) adduct formation, achieving high diastereoselectivity and yields under metal-free ambient conditions. Furthermore, successful functional group transformations and enantioselective catalytic attempts have been achieved using (R)-(+)-H8-BINOL.
Article
Chemistry, Applied
Fabian Scharinger, Matthias Weil, Michael Schnuerch, Katharina Bica-Schroeder
Summary: We introduce a simple method for the synthesis of chiral diazabicycloalkanes in a single reaction step. This method is applicable to a wide range of enals and has high functional group tolerance.
ADVANCED SYNTHESIS & CATALYSIS
(2023)
Article
Chemistry, Organic
Qijian Ni, Xuyang Wang, Da Zeng, Qianling Wu, Xiaoxiao Song
Summary: By using a chiral bifunctional squaramide catalyst, an asymmetric [3+3] cyclization of nitroenynes and 3-pyrrolyloxindoles has been achieved, providing an efficient access to enantioenriched polycyclic aza-spirooxindoles with 32-95% isolated yields and excellent stereocontrol under mild reaction conditions.
Article
Chemistry, Applied
Fushuai Li, Zhihong Yang, Yanyan Yang, Qiuhong Huang, Xuling Chen, Pengfei Li, Mingxin Dong, Wenjun Li
Summary: A chiral phosphorus acid catalyzed enantioselective 1,4-conjugate addition of arylamines to in situ formed 7-methylene-7H-indoles from 7-indolylmethanols has been successfully developed for the first time without the use of additives. The catalytic protocol enables the formation of 1,4-adducts with a nitrogen-containing tertiary carbon stereocenter in moderate to high yields and good enantioselectivity under mild reaction conditions.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Mengzhu Guo, Fengying Dong, Xiangcong Yin, Lubin Xu, Liang Wang, Shuai-Shuai Li
Summary: In this study, medicinally significant 3-monosubstituted tetrahydroquinolines and 1,2-dihydroquinolines were controllably constructed via a redox-neutral vinylogous cascade condensation/[1,5]-hydride transfer/cyclization process in ethanol, showcasing novel features such as green solvent and metal-free conditions. Additionally, the electrophilicity and nucleophilicity of alpha,alpha-dicyanoalkenes were effectively utilized as hydride acceptors and gamma-exclusive nucleophiles.
ORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Organic
August Runemark, Henrik Sunden
Summary: This paper reports a catalytic electron donor-acceptor (EDA) complex for visible light-driven annulation reaction between alkylated alkenes and N,N-substituted dialkyl anilines. Investigations into the mechanism reveal the rare example of a catalytic acceptor in photoactive EDA complexes that can give selective functionalization of aromatic amines under mild photochemical conditions.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Chao Liu, Xiangwen Tan, Lingzhi Zhan, Yaru Jing, Wanqing Wu, Zhuofeng Ke, Huanfeng Jiang
Summary: A novel and efficient strategy for synthesizing fused benzo-aza-oxa-[5-6-5] tetracycles with high yields and diastereoselectivities has been demonstrated. This strategy involves the synthesis of functionally divergent anilines and 3-butenoic acid with five chemical bonds constructed. Control experiments and DFT calculations were performed to support the proposed mechanism.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
