The author of 《Electron-Deficient Alkynes as Dipolarophile in Pd-Catalyzed Enantioselective (3 + 2) Cycloaddition Reaction with Vinyl Cyclopropanes》 were Ding, Wen-Ping; Zhang, Gao-Peng; Jiang, Yang-Jie; Du, Juan; Liu, Xiu-Yan; Chen, Di; Ding, Chang-Hua; Deng, Qing-Hai; Hou, Xue-Long. And the article was published in Organic Letters in 2019. SDS of cas: 5781-53-3 The author mentioned the following in the article:
The activated alkynes have been used successfully for the first time as the dipolarophile in the palladium-catalyzed asym. (3 + 2) cycloaddition, affording highly functionalized cyclopentenes in good to high yields with high chemoselectivities and good to high enantioselectivities. The introduction of an addnl. carbonyl group at the α-position of the alkynyl esters is the key to activating the carbon-carbon triple bond. The reaction process was investigated, and an inverse process of Pd-catalyzed (3 + 2) cycloaddition was observed In the experiment, the researchers used Methyl 2-chloro-2-oxoacetate(cas: 5781-53-3SDS of cas: 5781-53-3)
Methyl 2-chloro-2-oxoacetate(cas: 5781-53-3) belongs to acyl chlorides. Lacking the ability to form hydrogen bonds, acyl chlorides have lower boiling and melting points than similar carboxylic acids. For example, acetic acid boils at 118 °C, whereas acetyl chloride boils at 51 °C. Like most carbonyl compounds, infrared spectroscopy reveals a band near 1750 cm−1.SDS of cas: 5781-53-3
Referemce:
Chloride – Wikipedia,
Chlorides – an overview | ScienceDirect Topics