Modularly Evolved 2-AminoDMAP/Squaramides as Highly Active Bifunctional Organocatalysts in Michael Addition


Isik M., Unver M. Y. , TANYELİ C.

JOURNAL OF ORGANIC CHEMISTRY, cilt.80, ss.828-835, 2015 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Cilt numarası: 80 Konu: 2
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1021/jo5022597
  • Dergi Adı: JOURNAL OF ORGANIC CHEMISTRY
  • Sayfa Sayıları: ss.828-835

Özet

We report a new family of chiral bifunctional acid/base type organocatalysts, 2-aminoDMAP/Squaramides, which are proved to be highly active (1 mol % cat. loading) promoters in conjugate addition of dibenzoylmethane to various trans-beta-nitroalkenes. Steric demand of the catalysts was clearly seen by a set-by-set modulation of the squaramide unit through electronic and steric factors. The synergistic cooperation of 2-aminoDMAP "superbase" and sterically encumbered squaramide (H-bond donor) enabled complete conversion of a range of reactants into corresponding Michael adducts in a couple of hours with exquisite selectivities (up to 98% ee).