Photoinduced reaction of dichlorosilylene with acetylene: Matrix isolation FTIR spectroscopic study

• Published in: Journal of organometallic chemistry Vol. 962; p. 122270
• Main Authors: Boganov, Sergey E., Becerra, Rosa, Promyslov, Vladimir M., Shangin, Pavel G., Lalov, Andrey V., Egorov, Mikhail P., Walsh, Robin
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15-03-2022
• Subjects: Acetylene; Dichlorosilirene; Dichlorosilylacetylene; Dichlorosilylene; Matrix-isolation FTIR spectroscopy; Photoinduced reaction; Dichlorosilylene; Dichlorosilirene; Photoinduced reaction; Dichlorosilylacetylene; Acetylene; Matrix-isolation FTIR spectroscopy
• ISSN: 0022-328X; 1872-8561
• DOI: 10.1016/j.jorganchem.2022.122270

•The ability of silylenes to form complexes with alkynes is proven experimentally.•Photoinduced reaction of SiCl2 with C2H2 is observed for the first time.•SiCl2 adds to the C CC bond or inserts into a C-H bond of C2H2 under irradiation.•In the thermal reaction, SiCl2 only adds to the C CC bond of C2H2.
A matrix-isolation FTIR study of the reaction between SiCl2 and acetylene showed that at low temperatures, it stops at the stage of complexation between the reactants. This made it possible to examine a photochemical version of this reaction, which led to the simultaneous formation of 1,1-dichloro-1-silacycloprop-2-ene and 3,3-dichloro-3-silaprop-1-yne in comparable yields in contrast to the thermal reaction, which, according to quantum chemical calculations carried out here, results in the formation of 1,1-dichloro-1-silacycloprop-2-ene as the only primary product.
Synopsis. The reaction between SiCl2 and acetylene in Ar matrices stops at the stage of complexation. Subsequent photolysis of the complexes results in the formation of dichlorosilylacetylene and labile 1,1-dichlorosilirene in comparable amounts. [Display omitted]