Ruthenium complexes of aminophosphine ligands and their use as pre-catalysts in the transfer hydrogenation of aromatic ketones: X-ray crystal structure of thiophene-2-(N-diphenylthiophosphino)methylamine

Özkar, Saim
Yildirim, Leyla Tatar
Reaction of thiophene-2-methylamine with one or two equivalents of PPh2Cl in the presence of NEt3, proceeds in thf to give thiophene-2-(N-diphenylphosphino)methylamine, la and thiophene-2-(N, N-bis(diphenylphosphino))methylamine, 2a respectively, under anaerobic conditions. Oxidations of la and 2a with aqueous hydrogen peroxide, elemental sulfur or gray selenium in thf gives the corresponding oxides, sulfides and selenides [Ph2P(E)NHCH2-C4H3S] (E: O 1b, S 1c, Se 1d) and [(Ph2P(E))(2)NCH2-C4H3S], (E: O 2b, S 2c, Se 2d) respectively, in high yield. Furthermore, two novel Ru(II) complexes with the P-N ligands la and 2a were synthesized starting with the complex [Ru(eta(6)-p-cymene)(mu-Cl)Cl](2). The complexes were fully characterized by analytical and spectroscopic methods. P-31-{H-1} NMR, DEPT, H-1-13C HETCOR or H-1-H-1 COSY correlation experiments were used to confirm the spectral assignments. The molecular structure of thiophene-2-(N-diphenylthiophosphino)methylamine was also elucidated by single-crystal X-ray crystallography. Following activation by NaOH, compounds 3 and 4 catalyze the transfer hydrogenation of acetophenone derivatives to 1-phenylethanol derivatives in the presence of iso-PrOH as the hydrogen source. [Ru(Ph2PNHCH2-C4H3S)(eta(6)-p-cymene)Cl-2], 3 and [Ru((PPh2)(2)NCH2-C4H3S)-(eta(6)-p-cymene)Cl]Cl, 4 complexes are suitable catalyst precursors for the transfer hydrogenation of acetophenone derivatives in 0.1 M iso-PrOH solution. Notably 4 acts as an excellent catalyst giving the corresponding alcohols in excellent conversions up to 99% (TOF <= 744 h(-1)). This transfer hydrogenation is characterized by low reversibility under the experimental conditions.


Aminophosphine-palladium(II) complexes: Synthsesis, structure and applications in Suzuki and Heck cross-coupling reactions
AYDEMİR, MURAT; BAYSAL, AKIN; ŞAHİN, Ertan; Gumgum, Bahattin; Özkar, Saim (Elsevier BV, 2011-11-30)
Reaction of furfurylamine with 1 or 2 equivalents of PPh2Cl in the presence of Et3N, proceeds under anaerobic conditions in thf to give furfuryl-2-(N-diphenylphosphino)amine, Ph2PNHCH2-C4H3O, 1 and furfuryl-2-(N,N-bis(diphenylphosphino)amine), (Ph2P)(2)NCH2-C4H3O, 2, respectively. The reactions of 1 and 2 with MCl2(cod) (M = Pd, Pt; cod = 1,5-cyclooctadiene) or Pt(CH3)(2)(cod) yield complexes [M(Ph2PNHCH2-C4H3O)(2)Cl-2] (M= Pd 1a, Pt 1b), [Pt(Ph2PNHCH2-C4H3O)(2)(CH3)(2)] (1c), and [M((Ph2P)(2) NCH2-C4H3O)Cl...
Ruthenium(0) nanoparticles supported on xonotlite nanowire: a long-lived catalyst for hydrolytic dehydrogenation of ammonia-borane
Akbayrak, Serdar; Özkar, Saim (Royal Society of Chemistry (RSC), 2014-01-01)
Ruthenium(0) nanoparticles supported on xonotlite nanowire (Ru(0)@X-NW) were prepared by the ion exchange of Ru3+ ions with Ca2+ ions in the lattice of xonotlite nanowire followed by their reduction with sodium borohydride in aqueous solution at room temperature. Ru(0)@X-NW were characterized by a combination of advanced analytical techniques. The results show that (i) highly dispersed ruthenium(0) nanoparticles of 4.4 +/- 0.4 nm size were formed on the surface of xonotlite nanowire, (ii) Ru(0)@X-NW show hi...
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Citation Formats
M. AYDEMİR, A. BAYSAL, S. Özkar, and L. T. Yildirim, “Ruthenium complexes of aminophosphine ligands and their use as pre-catalysts in the transfer hydrogenation of aromatic ketones: X-ray crystal structure of thiophene-2-(N-diphenylthiophosphino)methylamine,” POLYHEDRON, pp. 796–804, 2011, Accessed: 00, 2020. [Online]. Available: