Results 51 to 60 of about 3,168 (214)

Synthesis of Bioactive Macrocycles Involving Ring-Closing Metathesis Strategy

SynOpen, 2023
This review reports the synthesis of various bioactive macrocycles, involving ring-closing metathesis as a key step, developed since ca. 2000. These macrocycles exhibited biological activities such as antiviral, antifungal, antibacterial, and anticancer ...
Nasrin Jahan, Inul Ansary
doaj   +1 more source

Beyond catalyst deactivation: cross-metathesis involving olefins containing N-heteroaromatics

Beilstein Journal of Organic Chemistry, 2015
Alkenes containing N-heteroaromatics are known to be poor partners in cross-metathesis reactions, probably due to catalyst deactivation caused by the presence of a nitrogen atom.
Kevin Lafaye, Cyril Bosset, Lionel Nicolas, Amandine Guérinot, Janine Cossy   +4 more
doaj   +1 more source

Total Synthesis of (-)-(7S,10R)-Calamenene and (-)-(7S,10R)-2-Hydroxycalamenene by Use of a Ring-Closing Metathesis Reaction. A Comparison of the cis- and trans-Isomers

Molecules, 2002
The title compounds have been synthesized starting from l-menthone by application of a ring-closing metathesis reaction to confirm their reported absolute and relative stereochemistry.
Yoshinori Asakawa, Fumihiro Nagashima, Motoo Tori, Masakazu Sono, Masashi Imoto, Katsuyuki Nakashima   +5 more
doaj   +1 more source

1,7‐Digallatetracarborane: Between Nucleophilic closo‐Cluster and “Inverse Sandwich” Digallylene

Angewandte Chemie, EarlyView.
A dianionic π‐ligand is used to make a Janus‐type twofold complex with low‐valent gallium Ga(+I). The resulting compound can be seen as and reveals the reactivity of both: a Wade‐type closo‐carborane cluster with nucleophilic Ga‐sites, as well as π‐ligand stabilized Ga(I) atoms in an inverse sandwich compound.
Julijan Sarcevic, Tobias Heitkemper, Niklas Mehner, Maximilian Kubis, Christian P. Sindlinger   +4 more
wiley   +2 more sources

Efficient catalytic alkyne metathesis with a fluoroalkoxy-supported ditungsten(III) complex

Beilstein Journal of Organic Chemistry, 2018
The molybdenum and tungsten complexes M2(OR)6 (Mo2F6, M = Mo, R = C(CF3)2Me; W2F3, M = W, R = OC(CF3)Me2) were synthesized as bimetallic congeners of the highly active alkyne metathesis catalysts [MesC≡M{OC(CF3)nMe3−n}] (MoF6, M = Mo, n = 2; WF3, M = W ...
Henrike Ehrhorn, Janin Schlösser, Dirk Bockfeld, Matthias Tamm   +3 more
doaj   +1 more source

A Synthetic Approach Toward a Brominated Oxocane Labdane Diterpenoid Isolated From

Natural Product Communications, 2020
The synthesis of a labdane oxocane epoxy-alcohol is described starting from the Wieland–Miescher ketone derivative via ring closing olefin metathesis of a diene derivative, targeting the total synthesis of a brominated oxocane labdane diterpenoid ...
Hisahiro Hagiwara, Shohei Fujiwara, Chikako Iibachi, Toshio Suzuki, Takashi Hoshi   +4 more
doaj   +1 more source

Heavier Alkyne‐Ni0 Complexes, [R2E2·Ni] (E = Sn, Pb), Exhibiting σ‐Complex Character

Angewandte Chemie, EarlyView.
Using a reductive group elimination strategy, heavier alkyne (LEEL; E = Sn, Pb) complexes of Ni0 are accessed. In contrast to classical alkyne coordination, these systems are best described as σ‐complexes, driven by ligand‐induced constraints and the established poor π‐bonding in heavier alkyne analogues.
Leopold Junge, Emeric Schubert, Israel Fernández, Terrance J. Hadlington   +3 more
wiley   +2 more sources

Nucleophilic Gallyl Anions Enable Ga─Au Bimetallic Ammonia Activation

Angewandte Chemie, EarlyView.
Unlocking gallyl nucleophiles: Counterion control enables formation of an unsupported gallyl─gold complex. Gold coordination induces a polarity switch at gallium, enabling cooperative activation of NH3 and related N─H/O─H substrates under mild conditions.
Hellen Videa, Keelan M. Byrne, Tobias Krämer, Antonio J. Martínez‐Martínez   +3 more
wiley   +2 more sources

Olefin Metathesis Reaction in Water and in Air Improved by Supramolecular Additives

Molecules, 2015
A range of water-immiscible commercially available Grubbs-type precatalysts can be used in ring-closing olefin metathesis reaction in high yields. The synthetic transformation is possible in pure water under ambient conditions.
Jasmine Tomasek, Miriam Seßler, Harald Gröger, Jürgen Schatz   +3 more
doaj   +1 more source

Tandem Ring‐Opening–Ring‐Closing Metathesis for Functional Metathesis Catalysts [PDF]

Angewandte Chemie International Edition, 2016
AbstractUse of a tandem ring‐opening–ring‐closing metathesis (RORCM) strategy for the synthesis of functional metathesis catalysts is reported. Ring opening of 7‐substituted norbornenes and subsequent ring‐closing metathesis forming a thermodynamically stable 6‐membered ring lead to a very efficient synthesis of new catalysts from commercially ...
Amit A. Nagarkar, Mohammad Yasir, Aurelien Crochet, Katharina M. Fromm, Andreas F. M. Kilbinger   +4 more
openaire   +6 more sources