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The Exxon process, also Kuhlmann- or PCUK – oxo process, is used for the hydroformylation of C6–C12 olefins. The process relies on cobalt catalysts. In order to recover the catalyst, an aqueous sodium hydroxide solution or sodium carbonate is added to the organic phase.
a) Doubly bridging and b) terminal oxo ligands. A transition metal oxo complex is a coordination complex containing an oxo ligand. Formally O 2–, an oxo ligand can be bound to one or more metal centers, i.e. it can exist as a terminal or (most commonly) as bridging ligands. Oxo ligands stabilize high oxidation states of a metal. [1]
In 1953 evidence was disclosed that it is the active catalyst for the conversion of alkenes, CO, and H 2 to aldehydes, a process known as hydroformylation (oxo reaction). [12] Although the use of cobalt-based hydroformylation has since been largely superseded by rhodium-based catalysts, the world output of C 3 –C 18 aldehydes produced by ...
Long chain oxo-alcohols are often prepared using alpha-olefins from the Shell higher olefin process, to give secondary alcohols such as isodecyl alcohol. [2] Key oxo alcohols that are sold in commerce include the following: 2-Methyl-2-butanol (2M2B) n-Butanol; 2-Ethylhexanol; 2-Propylheptanol; Isononyl alcohol; Isodecyl alcohol
Hydroxide is stabilized by coordination to metal cations. Some metal hydroxides, those featuring redox-active metal centers, can be oxidized to give metal oxo complexes. Attack of water on metal oxo centers represents one pathway for the formation of the O-O bond, leading to dioxygen.
The formation of the oxo-dimer is a process called oxolation: [4] 2 [L n MOH] ⇌ L n M−O−ML n + H 2 O, where L = ligand. Ultimately olation and oxolation lead to metal oxides: 2 [M(H 2 O) 6] 3+ → M 2 O 3 + 9 H 2 O + 6 H + Olation and oxolation are responsible for the formation of many natural and synthetic materials.
Typical catalysts are platinum, and redox-active oxides of iron, vanadium, and molybdenum. In many cases, catalysts are modified with a host of additives or promoters that enhance rates or selectivities. Important homogeneous catalysts for the oxidation of organic compounds are carboxylates of cobalt, iron, and manganese
The use of sparteine as a ligand (Figure 2, A) [33] favors nucleopalladation at the terminal carbon to minimize steric interaction between the palladium complex and substrate. The Quinox-ligated palladium catalyst is used to favor ketone formation when substrate contains a directing group (Figure 2, B). [34]