The Influence of Imidazolylidene Ligands with Bulky Resorcinarenyl Substituents on Catalysts for Suzuki-Miyaura Coupling

Kaloglu M., SEMERIL D., BRENNER E., MATT D., ÖZDEMİR İ., TOUPET L.

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, sa.7, ss.1115-1120, 2016 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: Sayı: 7
  • Basım Tarihi: 2016
  • Doi Numarası: 10.1002/ejic.201501238
  • Dergi Adı: EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.1115-1120
  • Anahtar Kelimeler: Calixarenes, Cavitands, N-Heterocyclic carbenes, Palladium, Cross-coupling, IMIDAZOLIUM SALTS, EFFICIENT LIGANDS, CROSS-COUPLINGS, ARYL CHLORIDES, COMPLEXES, BIARYLS, PRECURSORS
  • İnönü Üniversitesi Adresli: Evet

Özet

PEPPSI-type imidazolylidene palladium complexes having their carbenic ring N-substituted with an aryl ring and a cavity-shaped unit [25,26,27,28-tetrapropyloxycalix[4]aren-5-yl or 6(10),12(16),18(22)-tetramethylenedioxy-2,8,14,20-tetrapentylresorcin[4]aren-5-yl (TPR)] have been prepared and assessed in Suzuki-Miyaura cross-couplings. Remarkable efficiency in the coupling of aryl chlorides with sterically hindered arylboronic acids was observed for the carbene ligand having its N atoms (N1, N2) substituted by a mesityl and a TPR group, respectively. This good performance possibly arises from strong steric interactions between the pentyl-substituted cavitand unit and the catalytic centre, which favours reductive elimination. Two of the imidazolium salts used for complex synthesis were characterised by X-ray diffraction analysis.