Secondary amides undergo in situ silyl imidate formation mediated by TMSOTf and an amine base, followed by addition to acetal acceptors to provide N-acyl-N,O-acetals in good yields. An analogous, high-yielding reaction is observed with 2-mercaptothiazoline as the silyl imidate precursor. Competing reduction of the acetal to the corresponding methyl ether via transfer hydrogenation can be circumvented by the replacement of i-Pr2NEt with 2,6-lutidine under otherwise identical reaction conditions.

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Post-print Article

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Copyright © 2011, Elsevier. The definitive version is available at:

DOI: 10.1016/j.tetlet.2011.07.023

Full Citation:

Downey, C. Wade, Alan S. Fleisher, James T. Rague, Chelsea L. Safran, Megan E. Venable, and Robert D. Pike. "Synthesis of N-Acyl-N,O-Acetals from N-Aryl Amides and Acetals in the Presence of TMSOTf." Tetrahedron Letters 52, no. 37 (September 12, 2011): 4756-759. doi:10.1016/j.tetlet.2011.07.023.