Brønsted Acid-Catalyzed, Highly Enantioselective Addition of Enamides to In Situ<i>-</i>Generated<i>ortho</i>-Quinone Methides: A Domino Approach to Complex Acetamidotetrahydroxanthenes
作者:Satyajit Saha、Christoph Schneider
DOI:10.1002/chem.201406044
日期:2015.2.2
The highly enantioselective conjugate addition of enamides and enecarbamates to in situ‐generated ortho‐quinone methides, upon subsequent N,O‐acetalization, gives rise to acetamido‐substituted tetrahydroxanthenes with generally excellent enantio‐ and diastereoselectivities. A chiral BINOL‐based phosphoric acid catalyst controls the enantioselectivity of the carbon–carbon bond‐forming event. The products
A simple synthesis of benzofurans by acid-catalyzed domino reaction of salicyl alcohols with N-tosylfurfurylamine
作者:Anton A. Merkushev、Vladimir N. Strel'nikov、Maxim G. Uchuskin、Igor V. Trushkov
DOI:10.1016/j.tet.2017.09.043
日期:2017.11
A simple route to polysubstituted benzofurans based on the domino reaction of commercial or easily available salicyl alcohols with N-protected furfurylamine has been designed and developed. The reaction was found to proceed with reasonable yields under heating of substrates in acetic acid in the presence of catalytic amount of conc. HCl when tosyl was used as protecting group.