904922-22-1Relevant academic research and scientific papers
Thiazolium-catalyzed additions of acylsilanes: A general strategy for acyl anion addition reactions
Mattson, Anita E.,Bharadwaj, Ashwin R.,Zuhl, Andrea M.,Scheidt, Karl A.
, p. 5715 - 5724 (2006)
A strategy utilizing N-heterocyclic carbenes (NHCs) derived from thiazolium salts has been developed for the generation of carbonyl anions from acylsilanes. Synthetically useful 1,4-diketones and N-phosphinoyl-α- aminoketones have been prepared in good to excellent yields via NHC-catalyzed additions of acylsilanes to the corresponding α,β-unsaturated systems and N-phosphinoylimines. These organocatalytic reactions are air- and water-tolerant methods to execute robust carbonyl anion addition reactions. Additionally, polysubstituted aromatic furans and pyrroles have been efficiently synthesized in a one-pot process using this carbonyl anion methodology. The addition of alcohols to the reaction renders the process catalytic in thiazolium salt. In an effort to synthesize a potential intermediate along the proposed reaction pathway, silylated thiazolium carbinols have been identified to provide good yields of carbonyl anion addition products when subjected to the standard reaction conditions in the presence of suitable electrophiles.
Catalytic additions of acylsilanes to imines: An acyl anion strategy for the direct synthesis of α-amino ketones
Mattson, Anita E.,Scheidt, Karl A.
, p. 4363 - 4366 (2007/10/03)
(Chemical Equation Presented) The addition of acylsilanes to imines catalyzed by neutral carbenes (or zwitterions) generated in situ from readily available thiazolium salts is described. The general reaction successfully utilizes acylsilanes as carbonyl anion precursors and is tolerant of a range of structural diversity on the acylsilane or imine electrophile. The overall reaction utilizes easily available precursors and directly accesses protected α-amino ketones in the correct oxidation state.
