Piano-stool benzothiazol-2-ylidene Ru(II) complexes for effective transfer hydrogenation of carbonyls

Oruc Z. I., Gok L., TÜRKMEN H., ŞAHİN O., Buyukgungor O., Cetinkaya B.

JOURNAL OF ORGANOMETALLIC CHEMISTRY, vol.807, pp.36-44, 2016 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 807
  • Publication Date: 2016
  • Doi Number: 10.1016/j.jorganchem.2016.02.003
  • Journal Name: JOURNAL OF ORGANOMETALLIC CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Index Chemicus (IC)
  • Page Numbers: pp.36-44
  • Keywords: Benzothiazolium salts, NSHC-Ru(II) complexes, The transfer hydrogenation, Catalysis, N-HETEROCYCLIC CARBENE, ASYMMETRIC TRANSFER HYDROGENATION, BENZOTHIAZOLIN-2-YLIDENE COMPLEXES, RUTHENIUM COMPLEXES, CRYSTAL-STRUCTURE, PD(II) COMPLEXES, PALLADIUM(II), LIGANDS, KETONES, REDUCTION
  • Ondokuz Mayıs University Affiliated: Yes

Abstract

Benzothiazolium bromides (NSHC center dot HBr) (1a-j) with a variety of alkyl chain or benzyl substituents on N atom were prepared. The synthesis of ruthenium(II) (NSHC) complexes, (2a-j) could be achieved by in situ deprotonation of benzothiazolium salts with Ag2O and [RuCl2(p-cymene)](2). They were characterized by H-1, C-13, F-19 NMR, IR spectroscopy and elemental analysis. The molecular structures of 2d, 2e and 2g were ascertained by single-crystal X-ray diffraction studies. The catalytic properties of complexes, (2aej), with electron-donating or -withdrawing groups were investigated in transfer hydrogenation (TH) of ketones, and aldehydes with good to excellent yields. The presence of the CH2(CH2)(16)CH3 or CH2C6F5 on the N atom of the benzothiazol-2-ylidene complexes (2g, 2j) showed the highest activity for TH reaction. The catalytic properties of the N-alkyl substituted ruthenium(II) (NSHC) complexes(2h-j) may be interpreted by micelle effects. (C) 2016 Elsevier B.V. All rights reserved.