Key Reactions in Homogeneous Catalysis

The catalytic cyclo-oligomerization of 1,3-butadiene mediated by transition-metal complexes is one of the key reactions in homogeneous catalysis.1 Several transition metal complexes and Ziegler-Natta catalyst systems have been established that actively catalyze the stereoselective cyclooligomerization of 1,3-dienes.2 Nickel complexes, in particular, have been demonstrated to be the most versatile catalysts.3... 

In this account we have presented a consistent and theoretically well-founded view of the catalytic structure-reactivity relationships for the nickel-catalyzed cyclo-oligomerization of 1,3-butadiene, which represents one of the key reactions in homogeneous catalysis that, furthermore, has... 

Key Reactions in Homogeneous Catalysis 117 Table 2-1 Typical cone angles fortrivalent phosphorus ligands [20]... 

Table 1-4 shows in more detail that the key reactions of homogeneous catalysis, such as hydride elimination and oxidative addition, correspond to dissociative chemisorption in heterogeneous catalysis (see Section 2.1). 

The second rule can be depicted schematically for the key reactions of homogeneous catalysis as shown in Scheme 2-2. 

The involvement of transition-metal allenylidene complexes in homogeneous catalysis was reported for the first time by B. M. Trost and co-workers in 1992 (Scheme 35) [293-295]. The catalytic reactions allowed the preparation of a wide variety of tetrahydropyranyl and furanyl p,y-unsaturated ketones starting from hydroxy-functionalized alkynols and allylic alcohols, the key step in the catalytic... 

The book presents a review of sixteen important topics in modem homogeneous catalysis. While the focus is on concepts, many key industrial processes and applications that are important in the laboratory synthesis of organic chemicals are used as real world examples. After an introduction to the field, the elementary steps needed for an understanding of the mechanistic aspects of the various catalytic reactions have been described. Chapter 3 gives the basics of kinetics, thus stressing that kinetics, so often neglected, is actually a key part of the foundation of catalysis. 

There are an increasing number of applications of high pressure NMR in supercritical fluids to homogeneous catalysis [266]. Using their toroidal pressure probe, Rathke and coworkers [249, 267-269] have extensively studied the Co2(CO)g-cata-lyzed hydroformylation of olefins in scCOj (Eq. (14)). The hydrogenation of Co2(CO)g (Eq. (15)) is a key step in this reaction. 

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