Olefin metathesis overview

In this chapter I will cover only well-defined or well-characterized compounds. Results will be included that have appeared since reviews in 1991 on alkylidene and metalacyclobutane complexes [41] and in 1993 on ring-opening metathesis polymerization [30], but an overview of prior results that are especially relevant to olefin metathesis in particular will also be included. (An excellent and comprehensive text also has been published recently [1].) The terms well-defined or well-characterized originally were meant to imply that the alkylidene complex is isolable and is essentially identical to that in a catalytic reaction except for the identity of the alkylidene. These terms have been watered down from time to time in the literature, even to the point where they are used to describe a catalyst that is formed from a well-characterized transition metal precursor complex, but whose identity actually is not known. In this article I... 

For a previous brief overview of this Mo-catalyzed asymmetric olefin metathesis, see Hoveyda, AH, Schrock RR (2001) Chem Eur J 7 945... 

This chapter is concerned specifically with olefin metathesis reactions catalyzed by ruthenium-carbene complexes, mainly because of their great success during recent years. We begin with an overview of these catalysts, and then focus on mechanistic considerations that are important for understanding the reactivity profiles of various catalyst derivatives. The second part of the chapter deals with applications of ruthenium-catalyzed olefin metathesis, especially RCM, CM, and combination processes in organic synthesis. 

The reaction of a metal-carbene complex with an olefin may lead to either cyclopropane or metathesis products, depending on the metal center and its ancillary ligands. In the case of olefin metathesis, the reaction may occur in variations that have enormous numbers of synthetic applications. Although these products are diverse in structure, they are all related by the same basic metal-carbene-mediated mechanism of formation. Because we provide only an overview of applications in this section and do not specify the particular catalyst used in each case, we direct the reader to the extensive reviews that are available for more information [32]. 

R. H. Grubbs (2004) Tetrahedron, vol. 60, p. 7117 - Olefin metathesis gives an overview of the development and mechanistic details of Grubbs catalysts. 

This overview has given industrial applications of the olefin metathesis reaction. If most commercial applications have been listed, only some of the non-commercialized ones were given but even so some conclusions can be drawn ... 

Poly- and oligo-(p-phenylenevinylene) (PPV OPV) as well as their substituted derivatives belong to the conjugated systems with valuable opto-electronical properties [1] as a consequence, the preparation of highly regular PV-products is in the focus of interest of many research groups, worldwide. In this contribution an overview will be given about olefin metathesis as a tool for direct synthesis of PPV, OPV and of their substituted derivatives. Furthermore, results of the product characterization and the product properties will be presented exemplarily. 

Actually in the field of olefin metathesis the development of new initiators is very rapid particularly for Ru-based systems. Therefore, in this article we could only present a brief overview. For further Ru based initiators see, e.g.. Refs. [224-229]. Moreover, a variety of difunctional initiators were synthesized and employed for the synthesis of triblock... 

Abstract A ort general introduction combined with some historical milestones in the field of olefin metathesis is presented followed by an overview of recent representatives of metal carbene initiators. This paper attempts to relief the many supeib contributions and overwhehning woik invested in intelligent design and innovative synthesis in this area. Despites of recent advances there is still a great interest in the generation of new, better performing, and more environment fiiendly metathesis. 

On the other hand, our recent study on the highly efficient cross-metathesis of vinyltrialkoxy-and vinyltrisiloxy-silanes with various olefins, for example, with styrene [12] allyl eth [13] and esters [14] as well as octavinylsilsesquioxane [IS] with several olefins have opened a new opportunity for the use of alkene-cross-metathesis in the synthesis of unsaturated organosilicon compounds (see also Refs. [5] and [6]). In this p r new examples of the two reactions involving hetero(N,S,B)organic olefins have been overviewed. 

Because this book is devoted to fine chemical synthesis by heterogeneous catalysis, homogeneously catalyzed metathesis reactions will not be discussed. After a short overview of heterogeneous metathesis catalysts, the synthesis of fine chemicals from normal (unfunctionalized) olefins in the presence of these heterogeneous catalysts will be discussed. This is followed by a discussion of fine chemicals synthesized from functionalized olefins. 

In this contribution, we will overview reactivity modes and efficient synthetic routes based on metathesis transformations of vinylsilanes in the presence of Grubbs catalysts. The efficient cross-metathesis of vinylsilanes, carrying a large spectrum of different substituents at silicon, with various olefins in the presence of the first- and second-generation Grubbs catalyst and Hoveyda-Grubbs catalyst is described (Eq. 1). 

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