637337-86-1Relevant academic research and scientific papers
Stereoselective synthesis of (E)-trisubstituted α,β-unsaturated amides and acids
Feuillet, Fred J. P.,Cheeseman, Matt,Mahon, Mary F.,Bull, Steven D.
, p. 2976 - 2989 (2007/10/03)
Potassium alkoxides of N-acyl-oxazolidin-2-one-syn-aldols undergo stereoselective elimination reactions to afford a range of trisubstituted (E)-αβ-unsaturated amides in >95% de, that may be subsequently converted into their corresponding (E)-αβ-unsaturated acids or (E)-αβ-unsaturated oxazolines in good yield. syn-Aldols derived from αβ-unsaturated aldehydes gave their corresponding trisubstituted (E)-αβ-unsaturated-amides with poorer levels of diastereocontrol, whilst there was a similar loss in (E)-selectivity during elimination of syn-aldols derived from chiral aldehydes. These elimination reactions proceed via rearrangement of the potassium alkoxide of the syn-aldol to a 1,3-oxazinane-2,4-dione enolate intermediate that subsequently eliminates carbon dioxide to afford a trisubstituted (E)-αβ-unsaturated amide. The (E)-selectivity observed during the ElcB-type elimination step has been rationalised using a simple conformational model that employs a chair-like transition state to explain the observed stereocontrol. The Royal Society of Chemistry 2005.
An (E)-selective synthesis of trisubstituted (E)-α, β-unsaturated acid derivatives
Feuillet, Fred J. P.,Robinson, Diane E. J. E.,Bull, Steven D.
, p. 2184 - 2185 (2007/10/03)
Potassium alkoxides of N-acyloxazolidin-2-one derived synaldolates undergo a novel tandem intramolecular cyclisation elimination reaction to afford trisubstituted (E)-α,β-unsaturated amides in high d.e., which may be converted into their corresponding acids or oxazolines in good yield.
