112-91-4Relevant articles and documents
Highly Active and Selective Ru-PNH Catalyst in Aerobic Oxidation of Benzyl Amines
Aman, Michal,Tremmel, Jakub,Dostál, Libor,Erben, Milan,Tydlitát, Ji?í,Jansa, Josef,Jambor, Roman
, p. 4624 - 4630 (2019)
Set of [Ru(η6-cymene)(R)XCl] (R=L1SnCl, L1GeCl L2PPh2, X=Cl or SnCl3, L1=[2-(CH2NEt2)-4,6-(tBu)2C6H2]?, L2=2,6-iPr2-C6H3-NH?) catalysts was tested in aerobic oxidations of primary amines. The activity of studied catalysts depends on the charge of the Ru atom that has been influenced either by donating ligands R or by character of X. Typical Ru/P catalyst [Ru(η6-cymene)(L2PPh2)Cl2] (3) with least negative charge on the Ru atom has been observed as the most effective. The design of the phosphine ligand L2 containing amino-phosphine PNH moiety provided efficient anchoring of complex 3 to silica gel via hydrogen bonding of the PNH functional group to SiO2 to give heterogeneous catalyst 3-silica. This complex has been also efficiently tested in aerobic oxidation as recyclable catalyst with cumulative TON up to 6930.
Synthesis, characterization, catalytic and biological application of half-sandwich ruthenium complexes bearing hemilabile (κ2-: C, S)-thioether-functionalised NHC ligands
Achard, Thierry,Bellemin-Laponnaz, Stéphane,Chen, Weiguang,Egly, Julien,Maisse-Francois, Aline,Poblador-Bahamonde, Amalia I.
supporting information, p. 3243 - 3252 (2020/03/19)
A series of cationic Ru(ii)(η6-p-cymene) complexes with thioether-functionalised N-heterocyclic carbene ligands have been prepared and fully characterized. Steric and electronic influence of the R thioether substituent on the coordination of the sulfur atom was investigated. The molecular structure of three of them has been determined by means of X-ray diffractrometry and confirmed the bidentate (κ2-C,S) coordination mode of the ligand. Interestingly, only a single diastereomer, as an enantiomeric couple, was observed in the solid state for complexes 1c, 1i and 1j. DFT calculations established a low energy inversion barrier between the two diastereomers through a sulfur pyramidal inversion pathway with R donating group while a dissociative/associative mechanism is more likely with R substituents that contain electron withdrawing group, thus suggesting that the only species observed by the 1H-NMR correspond to an average resonance position of a fluxional mixtures of isomers. All these complexes were found to catalyse the oxydant-free double dehydrogenation of primary amine into nitrile. Ru complex bearing NHC-functionalised S-tBu group was further investigated in a wide range of amines and was found more selective for alkyl amine substrates than for benzylamine derivatives. Finally, preliminary results of the biological effects on various human cancer cells of four selected Ru complexes are reported.
Easy Ruthenium-Catalysed Oxidation of Primary Amines to Nitriles under Oxidant-Free Conditions
Achard, Thierry,Egly, Julien,Sigrist, Michel,Maisse-Fran?ois, Aline,Bellemin-Laponnaz, Stéphane
supporting information, p. 13271 - 13274 (2019/10/21)
A dehydrogenation of primary amine to give the corresponding nitrile under oxidant- and base-free conditions catalysed by simple [Ru(p-cym)Cl2]2 with no extra ligand is reported. The system is highly selective for alkyl amines, whereas benzylamine derivatives gave the nitrile product together with the imine in a ratio ranging from 14:1 to 4:1 depending on the substrate. Preliminary mechanistic investigations have been performed to identify the key factors that govern the selectivity.
