In industrial chemistry, carboalkoxylation is a process for converting

alkene In organic chemistry, an alkene is a hydrocarbon containing a carbon–carbon double bond. Alkene is often used as synonym of olefin, that is, any hydrocarbon containing one or more double bonds.H. Stephen Stoker (2015): General, Organic, an ...

s to

ester In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides ar ...

s. This reaction is a form of

carbonylation Carbonylation refers to reactions that introduce carbon monoxide into organic and inorganic substrates. Carbon monoxide is abundantly available and conveniently reactive, so it is widely used as a reactant in industrial chemistry. The term carbon ...

. A closely related reaction is hydrocarboxylation, which employs water in place of alcohols A commercial application is the carbomethoxylation of

ethylene Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula or . It is a colourless, flammable gas with a faint "sweet and musky" odour when pure. It is the simplest alkene (a hydrocarbon with carbon-carbon double bonds). Ethylene i ...

to give methyl propionate: :C₂H₄ + CO + MeOH → MeO₂CC₂H₅ The process is catalyzed by Pd ₆H₄(CH₂PBu-t)₂sub>2. Under similar conditions, other Pd-diphosphines catalyze formation of polyethyleneketone. Methyl propionate ester is a precursor to

methyl methacrylate Methyl methacrylate (MMA) is an organic compound with the formula CH2=C(CH3)COOCH3. This colorless liquid, the methyl ester of methacrylic acid (MAA), is a monomer produced on a large scale for the production of poly(methyl methacrylate) (PMMA ...

, which is used in plastics and adhesives. Carboalkoxylation has been incorporated into various

telomerization Telomerization is a reaction that produces a particular kind of oligomer with two distinct end groups. The oligomer is called a telomer. Some telomerizations proceed by radical pathways, many do not. A generic equation is: : A-B + n M -> A-M_ ...

schemes. For example carboalkoxylation has been coupled with the dimerization of 1,3- butadiene. This step produces a doubly unsaturated C9-ester: :2CH₂=CH-CH=CH₂ + CO + CH₃OH → CH₂=CH(CH₂)₃CH=CHCH₂CO₂CH₃

Hydroesterification

Related to carboalkoxylation is hydroesterification, the insertion of alkenes and alkynes into the H-O bond of carboxylic acids. Vinyl acetate is produced industrially by the addition of acetic acid to

acetylene Acetylene (systematic name: ethyne) is the chemical compound with the formula and structure . It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is unstable in its pure ...

in the presence of zinc acetate catalysts: Presently, zinc acetate is used as the catalyst: :

References

{{Reflist Chemical reactions Carbon monoxide