Insertion alkyl

A complete kinetic model of FTS over a state-of-the-art Co catalyst has been derived on the basis of the carbide theory and of CH2 insertion alkyl mechanism. 

Reaction of [Mn(R)(CO)j] with neutral nucleophiles is by far the most widely studied type of reaction for [Mn(R)(CO)s] compounds. The reaction usually involves addition of the neutral neucleophile, L, and is accompanied by CO insertion/alkyl migration to form an acyl species [Eq. (29)]. L is usually a tertiary phosphine (PR3), an alkylated amine (RNH2), or free carbon monoxide. Besides being a carbon-carbon bond forming reaction of fundamental importance, alkyl migration reactions of transition metal alkyl species have direct relevance to catalysis, especially for the 0X0 or hydroformylation process (2), the Monsanto acetic acid synthesis (2), and the synthesis of ethylene glycol (94). 

Insertion (alkyl migration) Reverse deinsertion bulky ligands... 

The Monsanto acetic acid process produces acetic acid from methanol and CO gas under fairly mild conditions (I80 C, 30-40 atm). The process utilizes a square planar Rh(l) catalyst. As shown in Figure 19.33, the first step in the catalytic mechanism is the OA of methyl iodide to form an 18-electron compound. In the second step, CO insertion (alkyl migration) occurs, resulting in a 16-electron species. Carbon monoxide adds to the vacant coordination site to r enerate a saturated compound, which then undergoes RE of CH3COI to regenerate the catalyst. The CH3COI product is further processed by reaction with water to make acetic acid and HI. The latter... 

Insertion of norbornene into a C-M bond is often reversible. For example, a jT-allylnickel norbornene complex was in equilibrium with inserted alkyl-nickel species (Scheme 1.33) [41]. Whereas the chloride complex favored the ir-allylnickel form, the acetate complex favored the inserted alkylnickel species. 

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 synthesis of a dicationic alkyl-olefin complex of Rh(iii) 339 allowed to study the effects of ligand geometry upon olefin insertion/alkyl migration, within a catalytic olefin polymerization reaction. ... 

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