Review
Chemistry, Organic
Waqar Ahmed, Vikrant Jayant, Shakeel Alvi, Nadeem Ahmed, Azeem Ahmed, Rashid Ali
Summary: The synthesis of natural products has always been a top priority for synthetic chemists worldwide. Various synthetic methodologies have been used to extract, elucidate, synthesize, and document a wide range of natural products. The synthesis of complex natural products often presents challenges that can be overcome through modification or development of new synthetic methods. Metathesis tactics, discovered unexpectedly in the 1950s and awarded the Nobel Prize in 2005, have greatly influenced and changed the landscape of total and formal synthesis. This review article provides a comprehensive detail of metathetic tools used in the synthesis of natural products from 2017 to 2019.
ASIAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Polymer Science
Mohammad Yasir, Andreas F. M. Kilbinger
Summary: Norbornene and cyclohexene show different polymerization behaviors using Grubbs' catalysts due to their varying ring strain energy levels; a sequence-selective cascade polymerization of a monomer containing both rings resulted in polymers with moderate molecular weight dispersities and good control over molecular weight.
Article
Chemistry, Multidisciplinary
Sarah N. Momm, Christian Seifried, Reinhard Brueckner
Summary: Previous studies have shown that 6,7-benzannulated nona-1,8-diene-5-ones can undergo ring-closing diene metatheses, giving benzotropolones. This study reveals that 6,7-benzannulated non-1-en-8-yn-5-ones can undergo ring-closing enyne metatheses, giving 9-vinylbenzotropolones. These findings are significant for organic synthesis.
Article
Chemistry, Multidisciplinary
Nils Ansmann, Thaddaus Thorwart, Lutz Greb
Summary: The Lewis superacid bis(perchlorocatecholato)silane catalyzes C-O bond metathesis of alkyl ethers with high efficiency, enabling chemoselective ring contractions of macrocyclic crown ethers and unprecedented ring-closing metathesis of polyethylene glycols for polymer-selective degradation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Luciana Sarmento Fernandes, Dalmo Mandelli, Wagner A. Carvalho, Elsa Caytan, Cedric Fischmeister, Christian Bruneau
Summary: The direct functionalization of sterically demanding alpha,alpha-disubstituted double bonds in beta-pinene, (-)-limonene and (-)-limonene terpenoids has been achieved through cross metathesis with internal olefins. This clean transformation provides a new method for accessing functionalized bulky cyclic terpenes, where the terminal double bond generates a trisubstituted olefin.
APPLIED CATALYSIS A-GENERAL
(2021)
Article
Chemistry, Organic
Philip Koblischek, Reinhard Brueckner
Summary: A series of reactions were used to synthesize benzocycloheptatrienones and 6,7-benzotropolones with different substitution patterns.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Dmitry S. Belov, Gabriela Tejeda, Charlene Tsay, Konstantin V. Bukhryakov
Summary: Vanadium-based catalysts have been demonstrated to catalyze ring-closing olefin metathesis reactions by well-defined V chloride alkylidene phosphine complexes, exhibiting good functional group tolerance. The properties of the imido group and phosphine were found to play a crucial role in the stability of active intermediates.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Organic
Andrea Ojeda-Porras, Remi Aouzal, Claire Wilson, Joelle Prunet
Summary: Two synthetic routes for the ABC tricycle of Taxol are presented, both involving a relay ring-closing metathesis reaction to form the central B ring. In the first approach, the extender arm is positioned on the A ring, while the C ring bears the relay tether in the second route. Despite the efficient synthesis of metathesis precursors with diverse extender arms, the crucial metathesis reactions failed to yield the target compounds in all cases.
Article
Polymer Science
Ankita Mandal, Indradip Mandal, Andreas F. M. Kilbinger
Summary: Regioselective chain transfer agents, in combination with the PA-ROMP technique, are used to synthesize narrowly dispersed heterotelechelic polymers with excellent control over molecular weight and dispersity. The chain transfer agents show high efficacy in 15 pulses of polymerization, with minimal catalyst decomposition and high degree of chain end functionalization confirmed by H-1 NMR and MALDI-ToF mass spectrometry.
Review
Chemistry, Multidisciplinary
Shrikant G. Pharande
Summary: Isocyanide-based multicomponent reactions (IMCR) and ruthenium-catalyzed ring-closing olefin metathesis (RCM) are powerful tools in organic synthesis, and their combination offers an efficient approach for the synthesis of complex cyclic olefins.
Article
Chemistry, Multidisciplinary
Myron Triantafyllakis, Sam Alexander, Sophie Woolford, Claire Wilson, J. Stephen Clark
Summary: The fully functionalized A-F fragment of the Pacific ciguatoxin CTX3C has been synthesized using specific reaction sequences and synthesis routes, achieving the construction of a multi-ring system and the introduction of functional groups.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Chemistry, Organic
Frank Schmidt, Aparna Viswanathan Ammanath, Friedrich Goetz, Martin E. Maier
Summary: A new synthesis route was established for the macrolactone antibiotic berkeleylactone A. The synthesis involved ring-closing alkyne metathesis (RCAM) of an ester substrate with 1-propynyl termini. The carboxylic part of the substrate was assembled using alkyne chemistry, while the alcohol part of the ester was synthesized through propylene oxide opening and triple bond migration reactions. After successful RCAM, the triple bond was selectively hydrogenated and the 4,5-diol was oxidized to obtain the desired derivative. The thioether formation and reduction of the 8,9-double bond were also achieved. However, the antimicrobial activity of the analog was found to be slightly reduced.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Sambasivarao Kotha, Deepshikha Singh, Vijayalakshmi Bandi
Summary: An efficient and short synthetic sequence for highly functionalized urazole derivatives has been reported. N-substituted-1,2,4-triazoline-3,5-dione (TAD) was used as a versatile synthetic reagent. Simple reactions including allylation, ring-closing metathesis, and hydrogenation were successfully employed to construct oxygenated urazole derivatives, which may have implications in medicinal chemistry and organic synthesis.
Article
Chemistry, Physical
Valerio Sabatino, Dario Staub, Thomas R. Ward
Summary: The synthesis of N-substituted indoles via ring-closing metathesis of indole precursors with N-terminal alkenes was reported. Good yields (up to 72%) were achieved in aqueous metathesis using commercial catalysts or artificial metalloenzymes. Furthermore, the presence of a second metathesis substrate increased the yield of N-acetylindole.
Review
Chemistry, Organic
Santhosh Kumar Podiyanachari, Hassan S. Bazzi, Mohammed Al-Hashimi
Summary: Synthesis of cycloolefin-based polymers via metathesis-accompanied cyclopolymerization and tandem ring-opening/ring-closing metathesis (RO/RCM) polymerization leads to highly functional cycloolefin ring-based polymers.
CURRENT ORGANIC CHEMISTRY
(2021)