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In organic chemistry, hydroformylation, also known as oxo synthesis or oxo process, is an industrial process for the production of aldehydes (R−CH=O) from alkenes (R 2 C=CR 2). [ 1 ] [ 2 ] This chemical reaction entails the net addition of a formyl group ( −CHO ) and a hydrogen atom to a carbon-carbon double bond .
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 [12] Although the use of cobalt-based hydroformylation has since been largely superseded by rhodium-based catalysts, the world output of C 3 –C 18 aldehydes produced by ...
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
It involves treatment of the alkene with a mixture of hydrogen gas and carbon monoxide in the presence of a metal catalyst. Illustrative is the generation of butyraldehyde by hydroformylation of propylene: H 2 + CO + CH 3 CH=CH 2 → CH 3 CH 2 CH 2 CHO. One complication with this process is the formation of isomers, such as isobutyraldehyde:
An example of this is the Tsuji–Wilkinson decarbonylation reaction using Wilkinson's catalyst. (Strictly speaking, the noncatalytic version of this reaction results in the formation of a rhodium carbonyl complex rather than free carbon monoxide.)
Often cross-coupling reactions require metal catalysts. One important reaction type is this: R−M + R'−X → R−R' + MX (R, R' = organic fragments, usually aryl; M = main group center such as Li or MgX; X = halide) These reactions are used to form carbon–carbon bonds but also carbon-heteroatom bonds.
In chemistry, an oxocarbon or oxide of carbon is a chemical compound consisting only of carbon and oxygen. [ 1 ] [ 2 ] The simplest and most common oxocarbons are carbon monoxide (CO) and carbon dioxide ( CO 2 ).
Also in the industrial process of (non-oxidative) dehydrogenation of ethylbenzene, the potassium-promoted iron oxide catalyst is coated with a carbon layer as the active phase. In another early example, [2] a variety of substituted nitrobenzenes were reduced to the corresponding aniline using hydrazine and graphite as the catalyst.