Alkenes, addition reactions overview

Several comprehensive reviews of photochemical SET reactions of amines are available, as are more specialized reviews of the reactions of amines with specific classes of excited states. - These include reviews of the photochemical reactions of amines with arenes and iminium ions, which appeared in the first edition of this Handbook. The present article provides an overview of the photochemical addition reactions of amines with alkenes. Detailed information about the mechanisms and dynamics of these reactions is provided in the original literature and the comprehensive reviews. 

Abstract The purpose of this chapter is to present a survey of the organometallic chemistry and catalysis of rhodium and iridium related to the oxidation of organic substrates that has been developed over the last 5 years, placing special emphasis on reactions or processes involving environmentally friendly oxidants. Iridium-based catalysts appear to be promising candidates for the oxidation of alcohols to aldehydes/ketones as products or as intermediates for heterocyclic compounds or domino reactions. Rhodium complexes seem to be more appropriate for the oxygenation of alkenes. In addition to catalytic allylic and benzylic oxidation of alkenes, recent advances in vinylic oxygenations have been focused on stoichiometric reactions. This review offers an overview of these reactions... 

Manganese(III)-mediated radical reactions have become a valuable method for the formation of carbon-carbon bonds over the past thirty years since the oxidative addition of acetic acid (1) to alkenes to give y-butyrolactones 6 (Scheme 1) was first reported by Heiba and Dessau [1] and Bush and Finkbeiner [2] in 1968. This method differs from most radical reactions in that it is carried out under oxidative, rather than reductive, conditions leading to more highly functionalized products from simple precursors. Mn(III)-based oxidative free-radical cyclizations have been extensively developed since they were first reported in 1984-1985 [3-5] and extended to tandem, triple and quadruple cyclizations. Since these additions and cyclizations have been exhaustively reviewed recently [6-11], this chapter will present an overview with an emphasis on the recent literature. 

The purpose of this section is to provide an overview of the principal kinetic features of the hydrogenation of ethene and of propene, as providing a framework (or at least part of one) within which discussion of mechanisms must be conducted. Their reactions with hydrogen (and with deuterium) are quite comparable the addition of the methyl group leads to somewhat higher reactivity, due to weaker chemisorption as might be predicted from its lower heat of hydrogenation (Table 7.1). Relative rates for other alkenes will be considered later. The problem of deactivation by carbon deposition has already been mentioned, but quantitative... 

Much work has also been conducted on the hydrosilylation of ketones and imines (Equation 16.16). The products from these reactions are silyl ethers and sdylamines. These additions of silanes across C-X ir-bonds have been conducted predominantly for the purpose of generating optically active alcohols and amines after hydrolysis. Because the mechanism of these reactions is less defined than the mechanism of alkene hydrosilylation, and this chemistry lies outside the theme of this chapter, the hydrosilylation of ketones and imines is presented only briefly. Instead, this chapter provides an overview of the scope and motivation for the hydrosilylation of alkenes and alkynes and provides details on the mechanisms of these reactions catalyzed by complexes of various metals. Several comprehensive reviews of the scope of these reactions have been published. ... 

Reactions of Alkenes—An Overview Organic Reactions Involving Reactive Intermediates Electrophilic Additions Hydroboration-Oxidation Oxidation... 

Chemists account for the addition of HX to an alkene by arrow pushing and a two-step mechanism, which we illustrate by the reaction of 2-butene with hydrogen bromide to give 2-bromobutane. We will first look at this two-step mechanism in overview and then go back and study each step in detail. 

We begin with a discussion of hydrogenation, focusing on the details of catalytic activation. Then we turn to the largest class of addition processes, those in which electrophiles such as protons, halogens, and metal ions are added to the alkene. Other additions that will contribute further to our synthetic repertoire include hydroboration, several oxidations (which can lead to complete mpture of the double bond if desired), and radical reactions. Each of these transformations takes us in a different direction the Reaction Summary Road Map at the end of the chapter provides an overview of the interconversions leading to and from this versatile compound class. 

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