Towards Stapling of Helical Alleno-Acetylene Oligomers - Synthesis of an Enantiopure Bis(ethynylvinylidene)-Substituted Cyclohexadeca-1,3,9,11-tetrayne

MUELLER I. -. S., BERNET B., Dengiz C., SCHWEIZER W. B., DIEDERICH F.

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, cilt.2014, sa.5, ss.941-953, 2014 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 2014 Sayı: 5
  • Basım Tarihi: 2014
  • Doi Numarası: 10.1002/ejoc.201301529
  • Dergi Adı: EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.941-953
  • Orta Doğu Teknik Üniversitesi Adresli: Hayır

Özet

We are interested in developing strategies to bridge (staple) enantiomerically pure acyclic alleno-acetylenic oligomers to enhance their conformational preferences for helical secondary structures, which are postulated to be at the origin of their exceptional chiroptical properties. We found that ring-closing metathesis (RCM), which has been used for the stapling of peptide helices, failed with an acyclic alleno-acetylene dimer decorated with lateral olefinic side chains. Instead, enyne RCM to an enantiomerically pure dienyne occurred. We switched to the introduction of diacetylene-containing bridges and report here the 15-step synthesis of a moderately strained, enantiomerically pure cyclohexa-1,3,9,11-tetrayne with an oxidative acetylenic coupling in the key step. The chiroptical properties of the new compounds are discussed.