Catalyst‐Free Trifluoromethoxylation of Silyl Enol Ethers and Allyl Silanes with Bis(trifluoromethyl)peroxide

• Published in: Angewandte Chemie International Edition Vol. 63; no. 7; pp. e202317770 - n/a
• Main Authors: Maas, Lilian M., Fasting, Carlo, Voßnacker, Patrick, Limberg, Niklas, Golz, Paul, Müller, Carsten, Riedel, Sebastian, Hopkinson, Matthew N.
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 12-02-2024
• Edition: International ed. in English
• Subjects: Allyl Silanes; Catalysts; Ethers; Fluorine; Ketones; Reagents; Room temperature; Silanes; Silyl Enol Ethers; Substrates; Trifluoromethoxylation; Allyl Silanes; Ketones; Trifluoromethoxylation; Fluorine; Silyl Enol Ethers
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202317770

Radical trifluoromethoxylation is an attractive approach to prepare compounds featuring the important OCF3 group, however most existing methods have focused on aromatic substrates. Here, we report novel methodologies with alkenyl substrates employing bis(trifluoromethyl)peroxide (BTMP) as a practical and comparatively atom economical trifluoromethoxylating reagent. With silyl enol ether substrates, switching reaction solvent allows for the synthesis of either α‐(trifluoromethoxy)ketone products or unprecedented alkenyl‐OCF3 species. Furthermore, allyl silanes have been employed as substrates for the first time, affording allyl(trifluoromethyl)ether products in good yields. In each case, the methods operate at room temperature without large excesses of the alkene substrate while, in contrast to previous radical trifluoromethoxylation reactions, no catalyst, light or other activators are required.
Catalyst‐free trifluoromethoxylation methods of alkenyl substrates under mild conditions have been developed using bis(trifluoromethyl)peroxide (BTMP) as a practical and relatively atom‐economical reagent. Silyl enol ether substrates react to form either α‐(trifluoromethoxy)ketones or OCF3‐containing silyl enol ethers depending on the solvent used while allyl silanes afford unprecedented allyl(trifluoromethyl)ethers.