Trimethylsilyl trifluoromethanesulfonate (TMSOTf) and a trialkylamine base promote the conversion of acetonitrile to its silyl ketene imine in situ when acetonitrile is employed as solvent. Residual TMSOTf acts as a Lewis acid catalyst to activate acetals and nitrones in the reaction mixture, yielding β-methoxynitriles and β-(silyloxy)aminonitriles, respectively. Some reaction products undergo elimination under the reaction conditions to provide the α,β-unsaturated nitrile directly.
Copyright © 2020, Tetrahedron Letters.
C. Wade Downey, Grace Ann L. Robertson, Jhonmattew Santa, Kari. R. Flicker, William M. Stith. One-pot silyl ketene imine formation-nucleophilic addition reactions of acetonitrile with acetals and nitrones. Tetrahedron Letters 2020, 61, Article 151537.