Enantioselective Synthesis of Cyclic, Quaternary Oxonitriles

Gunes Y., Polat M. F., ŞAHİN E., Fleming F. F., ALTUNDAŞ R.

JOURNAL OF ORGANIC CHEMISTRY, cilt.75, sa.21, ss.7092-7098, 2010 (SCI-Expanded) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 75 Sayı: 21
  • Basım Tarihi: 2010
  • Doi Numarası: 10.1021/jo1011202
  • Dergi Adı: JOURNAL OF ORGANIC CHEMISTRY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.7092-7098
  • Atatürk Üniversitesi Adresli: Evet

Özet

Quaternary oxonitriles are stereoselectively generated from the union of five-, six-, and seven-membered 2-chloroalkenecarbonitriles with chiral alcohols via a Claisen rearrangement. The strategy rests on a new conjugate addition elimination of allylic alkoxides to 2-chlorocycloalkenecarbonitriles to afford substituted 2-alkoxyalkenenitriles. Subsequent thermolysis unmasks a cyclic oxonitrile while selectively forming a new quaternary center with enantiomeric ratios typically greater than 9:I. The overall alkylation strategy addresses the challenge of enantioselectively generating hindered, quaternary centers while simultaneously installing ketone, nitrite, and olefin functionalities.