Abstract
Solvent-free iridium(iii)-catalyzed CO2 hydrosilylation to silylformate and kinetic modeling of such reaction are reported.
Highlights
The development of sustainable processes for carbon dioxide (CO2) reduction is a topic of general interest for the scientific community.[1]
Gas chromatography-mass spectrometry (GC-MS) spectra of the reaction samples taken after 3.5 days of reaction at 25 °C evidenced the full consumption of the starting HMTS and the presence of a peak with a retention time of 7.74 min corresponding to a major reaction product (Fig. 2 and Table 1)
We have found that the catalytic solvent-free reaction of CO2 (298 K, 3.0 bar) with HMTS to produce the corresponding silylformate was faster when complex 3 (1.0 mol%) was used instead of 1 as the catalyst precursor
Summary
The development of sustainable processes for carbon dioxide (CO2) reduction is a topic of general interest for the scientific community.[1] In particular, catalytic CO2 hydrosilylation represents a thermodynamically favorable process for the transformation of CO2 into value-added chemicals,[2] which presents the advantages that some hydrosilanes are easy to handle, readily available and environmentally harmless.[3] This CO2 fixation method allows formation of silylformates which have been successfully used as C1 building blocks in the synthesis of formic acid,[4] formamides,[5] amines,[6] and methane.[7] Selectivity is a relevant parameter to take into account when new catalysts for CO2 hydrosilylation to silylformates have to be designed This is due to the reactivity of silylformates, which under the reaction conditions could be hydrosilylated to afford the corresponding bis(silyl)acetal, which could react further with excess hydrosilane present in the reaction mixture to give methoxysilane and (R3Si)2O (Scheme 1).[8] the reaction of the corresponding methoxysilane with one additional equivalent of hydrosilane could lead to the formation of methane and (R3Si)2O (Scheme 1).[7] It is worth mentioning that some examples of transition metal catalysts as well as organocatalysts which selectively catalyze the hydrosilylation of CO2 to silylformates have been recently reported.4b,9–12 Among them, the phosphane–copper catalysts, using 1,4-dioxane as solvent, reported by Baba and co-workers are the most active known so far.[4]. We report a detailed kinetic study at variable temperature together with kinetic modeling of the catalytic hydrosilylation of CO2 with 1,1,1,3,5,5,5-heptamethyltrisiloxane (HMTS) using complex 3 as a catalyst precursor
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
