Review
Chemistry, Physical
Ming Bao, Michael P. Doyle
Summary: The [3+n]-cycloaddition reactions using chiral catalysts and racemic cyclopropanes or achiral catalysts and chiral, non-racemic cyclopropanes have proven to be important transformations for the synthesis of carbocyclic and heterocyclic compounds, showing both mechanistic and structural advantages in ring formation.
Article
Chemistry, Organic
Yujia Gao, Juan Zhang, Wenyu Shan, Weihong Fei, Jinzhong Yao, Weijun Yao
Summary: In this study, a trimerization reaction of gamma-aryl-3-butynoates was achieved through catalysis, leading to the formation of exocyclopentene derivatives with an allcarbon quaternary stereocenter. The reaction exhibited high stereoselectivity and enantioselectivity, delivering optically pure products with high enantiomeric excess values.
Article
Chemistry, Multidisciplinary
Nicola L. Oldroyd, Saurabh S. Chitnis, Etienne A. LaPierre, Vincent T. Annibale, Henry T. G. Walsgrove, Derek P. Gates, Ian Manners
Summary: The reactions of N-heterocyclic carbenes with polyaminoborane were studied, and the depolymerization process was found to be catalytic. The products of the reaction varied depending on the type of carbene used.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Xinyao Li, Johannes Grosskopf, Christian Jandl, Thorsten Bach
Summary: 3-Substituted quinoxalin-2(1H)-ones and various aryl-substituted or tethered olefins can undergo an enantioselective aza Paterno-Buchi reaction upon irradiation with a chiral sensitizer at lambda=420 nm. The absolute and relative configuration of the products were elucidated by X-ray crystallography, suggesting triplet energy transfer in a hydrogen-bonded complex between the imine substrate and the catalyst. Preliminary experiments also explored intramolecular cycloaddition and alternative reaction modes of quinoxalinones.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Review
Chemistry, Multidisciplinary
Rakshanda Singhal, Satya Prakash Choudhary, Babita Malik, Meenakshi Pilania
Summary: This review focuses on the recent synthetic advancements of N-tosylhydrazone under metal-free conditions for the construction of nitrogen-containing heterocycles. It discusses the selective, controllable, one-pot synthesis and wide substrate scope of N-tosylhydrazones.
Review
Chemistry, Multidisciplinary
Tingting Li, Zhichao Jin, Yonggui Robin Chi
Summary: This review discusses N-heterocyclic carbene-catalyzed reactions for the formation of aromatic compounds, categorizing them into 4 types based on activation modes. The achievements, challenges, and future research directions in NHC-catalyzed arene construction processes are summarized. The outlook is based on the authors' opinions and knowledge on the trends of NHC organocatalysis development.
SCIENCE CHINA-CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Wang Wang, M. Kevin Brown
Summary: In this study, we achieved the stereoselective construction of 3D bicyclic scaffolds and azetidine derivatives by modulating N-sulfonylimines, allowing for either [4+2]- or [2+2]-cycloaddition reactions. The utility of the method was demonstrated through further modulation of the resulting products. Mechanistic studies supported a reaction mechanism involving Dexter energy transfer.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Organic
Lona Dutta, Anwita Chattopadhyay, Nisha Yadav, S. S. V. Ramasastry
Summary: This study presents a metal-free strategy for the synthesis of various alpha-arylidene cyclopenta[b]indoles by phosphine-catalysed (3 + 2) annulation of alpha,beta-ynones and 3-nitroindoles. The rearomatisation of the indole nucleus was observed for the first time during this annulative transformation. The method was also applied to the synthesis of an antimalarial natural product, bruceolline E.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Review
Chemistry, Organic
Jiali Huang, Lei Zhang, Xiangtai Meng
Summary: Nitrogen- and sulfur-containing heterocyclic compounds are widely found in bioactive natural products and drug molecules. Efforts have been made to develop convenient and efficient strategies for synthesizing these compounds. Pyridinium zwitterions with unique reactivity have played a significant role in the construction of heterocycles. In recent years, these zwitterions have been extensively used in cyclization reactions to synthesize novel heterocyclic compounds.
ORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Applied
Guorong Xiao, Kaifu Wu, Wei Zhou, Qian Cai
Summary: A copper-catalyzed [3+2] cylcoaddition/ alkenyl C-N coupling tandem reaction was demonstrated, providing a method for the formation of triazolopiperidine skeletons.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Junhui Lin, Yannan Zhu, Wei Cai, You Huang
Summary: A domino [2+4]/[2+3] sequential annulation reaction of MBH carbonates with N-unprotected indoles has been developed, providing a straightforward approach for the synthesis of various pyrroloquinoline derivatives with high selectivity.
Review
Chemistry, Organic
Sudheesh T. T. Sivanandan, Mukkath J. J. Jesline, Divya K. K. Nair, Tarun Kumar
Summary: Organic transformations using visible light-mediated photoredox reactions have gained significant attention in recent years. Nitroalkenes have emerged as excellent coupling partners in these reactions, and various methodologies have been reported to achieve different types of alkenes and heterocycles. This review provides a summary of the synthetic potential of nitroalkenes under visible light photoredox catalysis, as a focused review on this topic has not yet appeared.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Vladimir A. Motornov, Andrey A. Tabolin, Sema L. Ioffe
Summary: A facile and versatile method for the synthesis of [5,5]-annulated N-fused heterocycles, pyrrolo[2,1-b]thiazoles and pyrrolo[1,2-b]indazoles, via oxidative [3+2] annulation of nitroalkenes and azolium ylides in the presence of copper(ii) has been developed. The reaction is performed under mild conditions using copper(ii) trifluoroacetate/2,6-lutidine system and gives moderate to good yields of the target N-fused heterocycles. Unique fluorinated derivatives can also be accessed using this methodology with alpha-fluoronitroalkenes.
NEW JOURNAL OF CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Deepti Gairola, Mohammad Saim Raza, Km Roshani, Rama Krishna Peddinti
Summary: A convenient and efficient metal-free oxidative [3+2] cycloaddition reaction has been developed using diacetoxyiodobenzene (DIB) as a hypervalent iodine reagent. N-arylmaleimides react with nitrile oxides generated in situ from the corresponding aldoximes, affording bioinspired bicyclic isoxazole/pyrrolo-isoxazole derivatives in high yields. The one-pot synthesis strategy demonstrated its potential in industrial application by scaling up the reaction to the gram-scale.
Article
Chemistry, Multidisciplinary
Chaohuang Chen, Constantin G. Daniliuc, Gerald Kehr, Gerhard Erker
Summary: The synthesis of element-carbon double bonds is described in this passage, focusing on the reactions with various molecules to form annulated heterocycles.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
