Hydroformylation 2-alkenes

Figure 2.21 Probable structure of the intermediate in alkene hydroformylation catalysed by...

In this account, the first systematic efforts toward hydrogen-mediated C-C couplings beyond alkene hydroformylation are described [52 - 54]. 

The discovery of the bisphospholane scaffold as a new privileged structure for asymmetric induction in alkene hydroformylation has triggered research for new and improved bisphospholane-type ligands. In this context (k,k)-Ph-bpc has been identified as an excellent ligand for asymmetric hydroformylation, which gives state-of-the-art regio- and enantioselectivities... 

Breit B (2007) Recent Advances in Alkene Hydroformylation. 279 139-172 Brizard A, Oda R, Hue I (2005) Chirality Effects in Self-assembled Fibrillar Networks. 256 167-218... 

Although most of the reports that have appeared since 1980 on hydroformylation of alkenes focus on rhodium catalysts, alkene hydroformylation catalyzed by Ptn complexes in the presence of Sn11 halides has been the object of great interest and platinum can be considered as the second metal in hydroformylation.77-79... 

Stoichiometric model reactions in alkene hydroformylation by platinum-tin systems have been studied for the independent steps involved in the hydroformylation process, insertion of the alkene, insertion of CO, and hydrogenolysis, with use of Pt-Sn catalysts and 1-pentene as alkene at low pressure and temperature.92... 

The less bulky ligand (71) studied by Gladfelter leads to dimeric complexes [Rh2(71)2(CO)2] and even tetramers.222 Transformations of rhodium carbonyl complexes in alkene hydroformylation are discussed from the standpoint of the catalytic system self-control under the action of reaction... 

The [HRh(CO)(TPPTS)3] precursor has opened a large area for the Supported-Aqueous-Phase (SAP) catalyzed functionalization of heavy substrates (see Chapter 9.9). Several ways to increase the efficiency of heavy alkene hydroformylation by Rh2(//-S-But)2(CO)2(TPPTS)2] have been investigated.424... 

Amidocarbonylation converts aldehydes into amido-substituted amino acids, which have many important industrial applications ranging from pharmaceuticals to detergents and metal-chelating agents.588 Two catalyst systems have been developed, a cobalt-based system and, more recently a palladium-based system. In the cobalt system, alkenes can be used as the starting material, thus conducting alkene-hydroformylation, formation of hemi-amidal and carbonylation in one pot as... 

The synthesis of aldehydes via hydroformylation of alkenes is an important industrial process used to produce in the region of 6 million tonnes a year of aldehydes. These compounds are used as intermediates in the manufacture of plasticizers, soaps, detergents and pharmaceutical products [7], While the majority of aldehydes prepared from alkene hydroformylation are done so in organic solvents, some research in 1975 showed that rhodium complexes with sulfonated phosphine ligands immobilized in water were able to hydroformylate propene with virtually complete retention of rhodium in the aqueous phase [8], Since catalyst loss is a major problem in the production of bulk chemicals of this nature, the process was scaled up, culminating in the Ruhrchemie-Rhone-Poulenc process for hydroformylation of propene, initially on a 120000 tonne per year scale [9], The development of this biphasic process represents one of the major transitions since the discovery of the hydroformylation reaction. The key transitions in this field include [10] ... 

In general, the mechanism of alkene hydroformylation with an [RhH(CO)P3] catalyst in water or in aqueous/organic biphasic systems (P = TPPTS) is considered to be analogous [61] to that of the same reaction in homogeneous organic solutions (P = PPh3) [84], a basic version of which is shown on Scheme 4.8. 

Rh Co4 (CO)i2 AI2O3 Impregnation and decarbonylation Highly dispersed Rh Co4 clusters high performance in alkene hydroformylation and C1-C2 alcohol synthesis in CO hydrogenation [140]... 

Alumina-supported catalysts prepared using the bimetallic carbonyl precursors showed a better performance in alkene hydroformylation than conventional Co-Rh catalysts. This was related to the presence of highly dispersed Rh-Co clusters with frames corresponding to that of the parent carbonyl-precursor that were characterized by EXAFS [140, 183]. Silica-supported bimetallic entities RhCo3,... 

Pronounced rate and selectivity enhancements had previously been observed for Ni(0)-catalyzed cyclodimerizations as well as rhodium-catalyzed alkene hydroformylation reactions. For related references see (Ni) van Leeuwen, P.W.N.M. Roobeek, C.F. Tetrahedron 1981, 37, 1973. (Rh) van Leeuwen,... 

The essential features of the alkene hydroformylation mechanism proposed by Heck and Breslow [61] remain intact, after many investigations using a variety of techniques. The cycle shown in Scheme 3.3 is that for the unmodified, cobalt... 

Scheme 3.3 Alkene hydroformylation mechanism for an unmodified cobalt catalyst.

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