Nickel-Catalyzed Reaction of Thioisatins and Alkynes: A Facile Synthesis of Thiochromones was written by Inami, Tasuku;Kurahashi, Takuya;Matsubara, Seijiro. And the article was included in Organic Letters in 2014.Safety of 1,4-Dimethoxy-2-butyne This article mentions the following:
A new synthetic method for thiochromones was developed by using nickel-catalyzed decarbonylative cycloaddition of readily available thioisatins with alkynes. This reaction proceeded under very mild conditions and has quite high functional group compatibility. In the experiment, the researchers used many compounds, for example, 1,4-Dimethoxy-2-butyne (cas: 16356-02-8Safety of 1,4-Dimethoxy-2-butyne).
1,4-Dimethoxy-2-butyne (cas: 16356-02-8) belongs to ethers. Relative to alcohols, ethers are generally less dense, are less soluble in water, and have lower boiling points. They are relatively unreactive. The unique properties of ethers (i.e., that they are strongly polar, with nonbonding electron pairs but no hydroxyl group) enhance the formation and use of many reagents. For example, Grignard reagents cannot form unless an ether is present to share its lone pair of electrons with the magnesium atom. Complexation of the magnesium atom stabilizes the Grignard reagent and helps to keep it in solution.Safety of 1,4-Dimethoxy-2-butyne
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem