Chemistry:Carboalkoxylation
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:[1]
- C
2H
4 + CO + MeOH → MeO
2CC
2H
5
The process is catalyzed by Pd[C
6H
4(CH
2PBu-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.[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:[3][4]
- 2 CH
2=CH–CH=CH
2 + CO + CH
3OH → CH
2=CH(CH
2)
3CH=CHCH
2CO
2CH
3
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 in the presence of zinc acetate catalysts:[5] Presently, zinc acetate is used as the catalyst:
- CH
3CO
2H + C
2H
2 → CH
3CO
2CHCH
2
Further reading
- Schoenberg, A.; Bartoletti, I.; Heck, R. F. (1974). "Palladium-catalyzed carboalkoxylation of aryl, benzyl, and vinylic halides". The Journal of Organic Chemistry 39 (23): 3318–3326. doi:10.1021/jo00937a003.
References
- ↑ Ahmad, Shahbaz; Bühl, Michael (2021-08-04). "Computational modelling of Pd-catalysed alkoxycarbonylation of alkenes and alkynes" (in en). Physical Chemistry Chemical Physics 23 (30): 15869–15880. doi:10.1039/D1CP02426D. ISSN 1463-9084. PMID 34318843. Bibcode: 2021PCCP...2315869A.
- ↑ Scott D. Barnicki (2012). "Synthetic Organic Chemicals". in James A. Kent. Handbook of Industrial Chemistry and Biotechnology (12th ed.). New York: Springer. ISBN 978-1-4614-4259-2.
- ↑ J. Grub; E. Löser (2012). "Ullmann's Encyclopedia of Industrial Chemistry". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a04_431.pub2.
- ↑ Kiss, Gabor (2001). "Palladium-Catalyzed Reppe Carbonylation". Chemical Reviews 101 (11): 3435–3456. doi:10.1021/cr010328q. PMID 11840990.
- ↑ Bienewald, Frank; Leibold, Edgar; Tužina, Pavel; Roscher, Günter (2019). "Ullmann's Encyclopedia of Industrial Chemistry". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. pp. 1–16. doi:10.1002/14356007.a27_419.pub2.
