Triazolium Salts as Lewis Acid Catalysts
Deepak Ranolia, Idan Avigdori, Kuldeep Singh, Aleksandr Koronatov, Natalia Fridman and Mark Gandelman*
*Schulich Faculty of Chemistry, Technion − Israel Institute of Technology, Technion City, Haifa 32000, Israel, Email: chmarktechnion.ac.il
D. Ranolia, I. Avigdori, K. Singh, A. Koronatov, N. Fridman, M. Gandelman, Org. Lett., 2022, 24, 3915-3919.
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Tetraaryl-1,2,3-triazolium salts are nitrenium-based Lewis acids. These salts catalyze the facile hydrosilylation-deoxygenation of ketones, aldehydes, acetals, alcohols, ethers, and silyl ethers under mild conditions in excellent yields.
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General procedure for triazolium-catalyzed hydrosilylations
Reaction conditions were optimized using acetophenone as standard substrate. The procedure is the same for all other substrates used for hydrosilylations. In a glovebox containing nitrogen atmosphere, a Schlenk tube was loaded with the acetophenone (0.1 mmol, 1 eq), PhSiH3 (0.3 mmol, 3 eq), the desired catalyst (5 mol%, 0.005 mmol, 0.05 eq), 1 ml of anhydrous DCM, and toluene (0.1 mmol, 1 eq) as internal standard. The Schlenk tube was then tightly sealed and removed from the glovebox. The mixture was stirred at 40°C for 2 hours and the yield was measured through 1H NMR (DMSO-d6 capillary added).