Heterobimetallic Complexes Bridged by Imidazol{[4,5-f][1,10]-phenanthrolin}-2-ylidene: Synthesis and Catalytic Activity in Tandem Reactions


Pezuk L. G., Sen B., Hahn F. E., TÜRKMEN H.

ORGANOMETALLICS, cilt.38, sa.2, ss.593-601, 2019 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 38 Sayı: 2
  • Basım Tarihi: 2019
  • Doi Numarası: 10.1021/acs.organomet.8b00882
  • Dergi Adı: ORGANOMETALLICS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.593-601
  • Dokuz Eylül Üniversitesi Adresli: Evet

Özet

A series of monometallic complexes obtained by metalation of the phenanthrolin donor in 1,3-dibutyl-1H-imidazol[4,5-f][1,10]phenanthrolin}ium hexafluorophospate 1 (M = Pd 2, Ru 3, Ir 4) have been prepared. Subsequently, the imidazolium moiety of complexes 2-4 was metalated with M', leading to the heterobimetallic phenanthroline/NHC complexes (M/M' = Pd/Rh 5, Pd/Ir 6, Pd/Ru 7, Ru/Pd 8, Ir/Pd 9) and the homobimetallic complex (M/M' = Ir/Ir 10). The new complexes were characterized by elemental analysis, FTIR, UV-vis, and NMR spectroscopy. The molecular structures of the heterobimetallic complexes 5 and 6 were determined by X-ray diffraction studies. The catalytic activity of the heterobimetallic complexes 5-9 were tested in selected tandem reactions (dehalogenation/transfer hydrogenation and Suzuki-Miyaura coupling/transfer hydrogenation). It was found that the M/M' heterobimetallic complexes display higher catalytic activities when compared to equimolar mixtures of the mononuclear complexes M and M', thus indicating that an increase in the number of metal atoms in one complex leads to an increased activity in the tandem reactions.