Results 191 to 200 of about 20,349 (227)

Organocatalytic Carbonyl-Olefin Metathesis

Journal of the American Chemical Society, 2012
The development of a catalytic carbonyl-olefin metathesis strategy is reported, in the context of the ring-opening metathesis of cyclopropenes with aldehydes using a simple hydrazine catalyst. The key to this reaction is a conceptual blueprint for metathesis chemistry that forgoes the traditional reliance on [2 + 2] cycloaddition modes in favor of a [3
Allison K, Griffith, Christine M, Vanos, Tristan H, Lambert   +2 more
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Olefin Metathesis. III.

Journal of Japan Oil Chemists' Society, 1976
In the homogeneous metathesis of 2-heptene catalyzed by WCl6-Et3Al and WCl6-R4Sn systems, the influence of the reaction medium on the conversion was investigated. Many kinds of halogenated hydrocarbon were found to be the more excellent medium than benzene and chlorobenzene.
Kazuaki ICHIKAWA, Toru TAKAGI, Kazuo FUKUZUMI   +2 more
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Organocatalyzed Carbonyl–Olefin Metathesis

Angewandte Chemie International Edition, 2013
The heat is on: A new [3+2] cycloaddition/cycloreversion strategy allows for catalytic and thermally allowed carbonyl-olefin metathesis (see scheme). This strategy opens opportunities for new developments in the field of carbonyl-olefin metathesis, which traditionally relied on stoichiometric amounts of transition-metal reagents or photochemical ...
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Olefin metathesis in carotenoid synthesis

Organic & Biomolecular Chemistry, 2009
Olefin metathesis is a powerful and widely applicable synthetic method for carbon-carbon double bond formation. However, its application to the synthesis of conjugating polyene chains has been very limited because of possible undesired side reactions. We attempted to apply this method to the synthesis of symmetrical carotenoids.
Takayuki, Kajikawa, Naoko, Iguchi, Shigeo, Katsumura   +2 more
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Olefin Metathesis Reactions

2005
This chapter contains sections titled: Highly active ruthenium (pre)catalysts for metathesis reactions A highly active and readily recyclable olefin metathesis catalyst Stereoselective synthesis of L-733,060.
Syuzanna Harutyunyan, Anna Michrowska, Karol Grela, Stephen J. Connon, Aideen M. Dunne, Siegfried Blechert, G. Bhaskar, B. Venkateswara Rao   +7 more
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Enamide−Olefin Ring-Closing Metathesis

Organic Letters, 2001
[reaction: see text] The first examples of ring-closing metathesis reactions of olefin-containing enamides using ruthenium-based catalysts have been demonstrated. A preliminary investigation into the scope and limitations, leading to protected five- and six-membered cyclic enamides, will be presented.
Kinderman, S.S., van Maarseveen, J.H., Schoemaker, H.E., Hiemstra, H., Rutjes, F.P.J.T.   +4 more
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Olefin Cross-Metathesis

2007
Olefin cross-metathesis has become an indispensable tool for efficient carbon–carbon bond formation. Fundamental studies on functional group tolerance and an understanding of the steric and electronic factors crucial to product selectivity have led to the development of an empirical model for reaction design.
Grubbs, R. H., Wenzel, A. G., Chatterjee, A. K.   +2 more
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Mechanochemical Ruthenium-Catalyzed Olefin Metathesis

Journal of the American Chemical Society, 2015
We describe the development of a mechanochemical approach for Ru-catalyzed olefin metathesis, including cross-metathesis and ring-closing metathesis. The method uses commercially available catalysts to achieve high-yielding, rapid, room-temperature metathesis of solid or liquid olefins on a multigram scale using either no or only a catalytic amount of ...
Do, Jean-Louis, Mottillo, Christina, Tan, Davin, Štrukil, Vjekoslav, Friščić, Tomislav   +4 more
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Metathesis of Olefins

ChemInform, 2006
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
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Functionalised olefin metathesis

Journal of Molecular Catalysis, 1988
Abstract A review is given of recent developments and applications of functionalised olefin metathesis in synthetic chemistry, analytical chemistry and biochemistry. Main problems in synthetic applications are the low reaction rate and the poor stereoselectivity of most metathetic conversions.
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