Methyl 4-chloro-4-oxobutanoate

Clear colorless to pale yellow liquid

Methyl 4-chloro-4-oxobutanoate acts as a synthetic precursor that reacts with indoline to yield the corresponding methyl ester derivative, and serves to generate ketene in situ for constructing cyclobutane rings via [2+2] cycloaddition with alkyl vinyl ethers[1-2].

Journal of the American Chemical Society, 75, p. 3339, 1953 DOI: 10.1021/ja01110a014
Organic Syntheses, Coll. Vol. 3, p. 169, 1955

[1] Zhao, Y., Svensson, F., Steadman, D., Frew, S., Monaghan, A., Bictash, M., Moreira, T., Chalk, R., Lu, W., Fish, P. V., & Jones, E. Y. (2021). Structural Insights into Notum Covalent Inhibition. Journal of Medicinal Chemistry, 64(15), 11354–11363. https://doi.org/10.1021/acs.jmedchem.1c00701
[2] Nosyk, D. A., Lukyanenko, S. Y., Granat, D. S., Skrypnik, D., Chigrinov, V., Liashuk, O. S., Shishkina, S. V., Savchenko, T., Yurchenko, O. O., & Grygorenko, O. O. (2025). Synthesis and Physicochemical Characterization of 2‐Azabicyclo[3.2.0]heptane Building Blocks. European Journal of Organic Chemistry, 28(47). https://doi.org/10.1002/ejoc.202500970