An effective hydrosilylation of alkynes in supercritical CO2 – A green approach to alkenyl silanes was written by Stefanowska, Kinga;Franczyk, Adrian;Szyling, Jakub;Salamon, Katarzyna;Marciniec, Bogdan;Walkowiak, Jedrzej. And the article was included in Journal of Catalysis in 2017.Reference of 16356-02-8 This article mentions the following:
Hydrosilylation of a wide group of alkynes (terminal and internal) with four structurally different silanes was for the 1st time performed in supercritical CO2 (scCO2). The results clearly showed the advantages as well as the limitations of using of scCO2 as a reaction and extraction medium for hydrosilylation of numerous alkynes with different functionality and volatility. Procedures for the synthesis and isolation of over forty silyl ethenes were described, among which more than twenty for the 1st time. Obtained products were fully characterized by 1H, 13C, 29Si NMR, GC-MS, and EA. Also, by x-ray crystallog., the mol. structures of (E)-3-(1,1,1,3,5,5,5-heptamethyltrisiloxan-3-yl)-2,5-dimethylhex-3-ene-2,5-diol (3n) and (E)-triethyl(2-(triphenylsilyl)vinyl)silane (12a) were determined for the 1st time. In the experiment, the researchers used many compounds, for example, 1,4-Dimethoxy-2-butyne (cas: 16356-02-8Reference of 16356-02-8).
1,4-Dimethoxy-2-butyne (cas: 16356-02-8) belongs to ethers. Of all the functional groups, ethers are the least reactive ones. Ether bonds are quite stable towards bases, oxidizing agents and reducing agents. But on the other hand, ethers undergo cleavage by reaction with acids. Ethers feature bent C閳ユ彊閳ユ弲 linkages. In dimethyl ether, the bond angle is 111鎺?and C閳ユ彊 distances are 141 pm. The barrier to rotation about the C閳ユ彊 bonds is low. The bonding of oxygen in ethers, alcohols, and water is similar. In the language of valence bond theory, the hybridization at oxygen is sp3.Reference of 16356-02-8
Referemce:
Ether – Wikipedia,
Ether | (C2H5)2O – PubChem