Carboalkoxylation

{{Short description|Process for converting alkenes to esters}}

In industrial chemistry, carboalkoxylation is a process for converting alkenes to esters. This reaction is a form of carbonylation. A closely related reaction is hydrocarboxylation, which employs water in place of alcohols.

A commercial application is the carbomethoxylation of ethylene to give methyl propionate:{{Cite journal |last1=Ahmad |first1=Shahbaz |last2=Bühl |first2=Michael |date=2021-08-04 |title=Computational modelling of Pd-catalysed alkoxycarbonylation of alkenes and alkynes |journal=Physical Chemistry Chemical Physics |language=en |volume=23 |issue=30 |pages=15869–15880 |issn=1463-9084 |doi=10.1039/D1CP02426D |pmid=34318843 |bibcode=2021PCCP...2315869A |s2cid=236472958 |doi-access=free|hdl=10023/23678 |hdl-access=free }}

:{{chem2|C2H4 + CO + MeOH → MeO2CC2H5}}

The process is catalyzed by {{chem2|Pd[C6H4(CH2PBu\-t)2]2}}. Under similar conditions, other Pd-diphosphines catalyze formation of polyethyleneketone.

Methyl propionate ester is a precursor to methyl methacrylate, which is used in plastics and adhesives.{{cite book |author=Scott D. Barnicki |chapter=Synthetic Organic Chemicals |title=Handbook of Industrial Chemistry and Biotechnology |editor=James A. Kent |place=New York |publisher=Springer |year=2012 |edition=12th |isbn=978-1-4614-4259-2}}

Carboalkoxylation has been incorporated into various telomerization schemes. For example carboalkoxylation has been coupled with the dimerization of 1,3-butadiene. This step produces a doubly unsaturated C9-ester:{{Ullmann |title=Butadiene |author1=J. Grub |author2=E. Löser |year=2012 |doi=10.1002/14356007.a04_431.pub2}}{{cite journal |doi=10.1021/cr010328q |title=Palladium-Catalyzed Reppe Carbonylation |year=2001 |last1=Kiss |first1=Gabor |journal=Chemical Reviews |volume=101 |issue=11 |pages=3435–3456 |pmid=11840990}}

:{{chem2|2 CH2\dCH\sCH\dCH2 + CO + CH3OH → CH2\dCH(CH2)3CH\dCHCH2CO2CH3}}