Hydroformylation and Carbonylation

Nickel catalysts are known to be effective in the carbonylation of aromatic halides  

A study of this carbonylation reaction catalysed by tetracarbonylnickel in polar aprotic solvents, e.g. dimethyl sulphoxide or iVA-dimethylformamide, in the presence of calcium hydroxide reveals that the reaction can proceed at one atmosphere pressure of carbon monoxide and at 100 °C. The reaction probably involves oxidation-addition of aryl halide to the nickel followed by carbon monoxide insertion. Rates decrease in the order I Br Cl F, Chloride ions and bromide ions enhance the reaction and this explains the autocatalytic behaviour observed as these ions are released from the aryl halide during reaction.  

The rates of olefin hydrogenation and isomerization by Group VIII metal-phosphine complexes are increased by the presence of hydroperoxides and/or oxygen. A similar rate enhancement is observed in the hydroformylation of alkenes catalysed by [RhCl(CO)(PPh3)2]. The addition of small amounts of cyclohexenyl hydroperoxide is considered to effect the unusual transformation of [RhCl(CO)(PPh3)2] to cw-[RhCl(CO)2(PPh3)], which appears to be a very active alkene hydroformylation and isomerization catalyst. Asymmetric induction in hydroformylation reactions has been achieved.  

Tanaka, Y. Watanabe, T. Mitsudo, A. Yamamoto, and Y. Takegami, Chem, Letters, 

The results of carbonylation of cis- and trans-hvA-l-enc in methanol in the presence of palladium(u)-copper(n) Wacker type catalyst show that in the initial stages of reaction, stereospecific fra/w-methoxypalladation is observed giving exclusively the threo- and ery/Aro-methoxyesters, respectively,  

Speert, J. Gelan, M. Anteunis, A. P. Marchand, and P. Laszlo, Tetrahedron Letters, 1973, 2271. 

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The use of catalytic SILP materials has been reviewed recently [10] covering Friedel-Crafts reactions [33-37], hydroformylations (Rh-catalyzed) [38], hydrogenation (Rh-catalyzed) [39,40], Heck reactions (Pd-catalyzed) [41], and hydroaminations (Rh-, Pd-, and Zn-catalyzed) [42]. Since then, the SILP concept has been extended to additional catalytic reactions and alternative support materials. In this paper we will present results from continuous, fixed-bed carbonylation and hydroformylation reactions using rhodium-based SILP catalysts as reaction examples demonstrating the advantages of the SILP technology for bulk chemical production. 

The most intensely studied insertion reactions are those of CO into metal—carbon bonds to form metal acyls. These reactions are fundamental to industrially important catalytic reactions such as carbonylation and hydroformylations (Sections 22-5 and 22-6). 

S. Kanagasabapathy, Studies in Oxidative Carbonylation and Hydroformylation Reactions Using Transition Metal Catalysts, Ph. D. Thesis, University of Pune,... 

Carbonylation and hydroformylation. With PEG as a PTC, COjCCO), mediates the carbonylation of benzylic halides. A more complex system is used in the transformation of propargylic alcohols into 2-alkylidenesuccinic acids (9 examples, 84-97%). Very similar results are obtained from the carbonylation of alkynyl ketones. "... 

Hydroformylation is the reaction of carbon monoxide and hydrogen with olefins to produce aldehydes and derivative alcohols. It is also known as 0X0 chemistry and the alcohol products produced by this method are known as 0X0 alcohols. Of all three types of carbon monoxide reactions, Reppe reactions, Koch carbonylations, and hydroformylations, oxo chemistry currently has the greatest commercial importance. An extremely broad range of products and end use markets are served by the aldehydes, alcohols, and derivatives produced by hydroformylation. The list of products shown in Table 6 illustrates the range of oxo chemical products. 

These Redox reactions include dehydrogenation reactions, oxidation reactions and also carbonylation and hydroformylation reactins where CO/H2 insertion occurs via oxidative addition, rearrangement within the oxidized form complex sphere and final reductive elimination of the products. 

However, with the exception of carbonylation and hydroformylation, most of these redox reaction require temperatures within 200°C or above yet a pionneer work has appeared certainty too early again dealing with the oxidation of an organic substrate with molecular oxygen at almost room temperature and sub atmospheric pressure. 

CARBON MONOXIDE INSERTION CARBONYLATION AND HYDROFORMYLATION REACTIONS... 

Dendritic catalysis have been used in various chemical reactions, including the Suzuki-Miyaura reaction, Mizoroki-Heck reaction, hydrogenation reaction, carbonylation and hydroformylation reactions, oxidation reaction, polymerization and oligomerization reactions, arylation reaction, alkylation reaction, and asymmetric synthesis [6]. Recently, dendritic catalysts have been reviewed by Astmc et al. [6], In another review article. Reek et al. reviewed the applications of dendrimers as support for recoverable catalysts and reagents [58]. The authors believed that catalytic performance in these systems depends on used dendritic architecture. 

Recall that there are a number of reactions where homogeneous catalysis involves two phases, liquid and gas, for example, hydrogenation, oxidation, carbonylation, and hydroformylation. The role of diffusion becomes important in such cases. In Chapter 6, we considered the role of diffusion in solid catalyzed fluid-phase reactions and gas-liquid reactions. The treatment of gas-liquid reactions makes use of an enhancement factor to express the enhancement in the rate of absorption due to reaction. A catalyst may or may not be present. If there is no catalyst, we have a simple noncatalytic gas-liquid heterogeneous reaction in which the reaction rate is expressed by simple power law kinetics. On the other hand, when a dissolved catalyst is present, as in the case of homogeneous catalysis, the rate equations acquire a hyperbolic form (similar to LHHW models discussed in Chapters 5 and 6). Therefore, the mathematical analysis of such reactions becomes more complex. 

Group VIII Metals.—The majority of catalysts reported for homogeneous hydration, carbonylation, and hydroformylation are compounds of these nine metals, particularly of cobalt, rhodium, and palladium. 

Carbon Monoxide.—Some examples of carbon monoxide insertion (alkyl migrations) have been mentioned in the discussion of carbonylation and hydroformylation reactions in the previous chapter (Part IV, Chapter 3, Section 10). The remaining reports will be treated here in Periodic Table order. 

The coordination chemistry of the cobalt triad has received considerable attention in the areas of organometallic reaction mechanisms and homogeneous catalysis (82-84), Of particular interest have been processes such as hydrogenation, carbonylation, and hydroformylation, where the oxidative addition of substrate C-X or H-X bonds to coordinatively-unsaturated M(I) centers plays a critical role. Systems which have received the most attention thus far have been electron-rich... 

First, there are a number of homogeneous catalytic reactions, such as carbonylation and hydroformylation (see Chapters 4 and 5), where carbon monoxide is used as one of the reactants. Coordinated carbon monoxide, as mentioned earlier, has a strong characteristic IR absorption that is sensitive to the electronic environment of the complex. The compositional or structural changes of carbonyl complexes result in a change in the carbonyl region of the IR spectra. 

The influences of diphosphines Ph2P(CH2) PPh2 on the rhodium-catalyzed carbonylation and hydroformylation of methanol to acetic add and acetaldehyde has been examined. [(P-P)Rhl(CO)] reacts with Mel to give the unstable but detectable Rh(III) complex [(P-P)RhMe(I)2CO], which is readily converted into [(P-P)Rh(COMe)l2]. The latter can be isolated after catalytic runs and liberates CH3CHO on treatment with hydrogen. The reaction is first order in [Rh—COMe] and zero order in [Mel]. The... 

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