Isomeric [RuCl2(dmso)2(indazole)2] complexes: ruthenium(II)-mediated coupling reaction of acetonitrile with 1H-indazole.
Reaction of the antitumor complex trans-[Ru(III)Cl4(Hind)2]- (Hind = indazole) with an excess of dimethyl sulfoxide (dmso) in acetone afforded the complex trans,trans,trans-[Ru(II)Cl2(dmso)2(Hind)2] (1). Two other isomeric compounds trans,cis,cis-[Ru(II)Cl2(dmso)2(Hind)2] (2) and cis,cis,cis-[Ru(II)Cl2(dmso)2(Hind)2] (3) have been obtained on refluxing cis-[Ru(II)Cl(2)(dmso)(4)] with 2 equiv. of indazole in ethanol and methanol, respectively. Isomers 1 and 2 react with acetonitrile yielding the complexes trans-[Ru(II)Cl2(dmso)(Hind){HN=C(Me)ind}].CH3CN (4.CH3CN) and trans,cis-[Ru(II)Cl2(dmso)2{HN=C(Me)ind}].H2O (5.H2O), respectively, containing a cyclic amidine ligand resulting from insertion of the acetonitrile C triple bond N group in the N1-H bond of the N2-coordinated indazole ligand in the nomenclature used for 1H-indazole. These are the first examples of the metal-assisted iminoacylation of indazole. The products isolated have been characterized by elemental analysis, IR spectroscopy, UV-vis spectroscopy, electrospray mass-spectrometry, thermogravimetry, differential scanning calorimetry, 1H NMR spectroscopy, and solid-state 13C CP MAS NMR spectroscopy. The isomeric structures of 1-3 and the presence of a chelating amidine ligand in 4 and 5 have been confirmed by X-ray crystallography. The electrochemical behavior of 1-5 and the formation of 5 have been studied by cyclic voltammetry.
Institute of Inorganic Chemistry-Bioinorganic, Environmental and Radiochemistry, Faculty of Chemistry, University of Vienna, A-1090 Vienna, Austria.
Erwin
E
Reisner
Vladimir B
VB
Arion
Anna
A
Rufińska
Ion
I
Chiorescu
Wolfgang F
WF
Schmid
Bernhard K
BK
Keppler
D000097:Acetonitriles / Q000737:chemistry*; D000970:Antineoplastic Agents / Q000138:chemical synthesis*; D002244:Carbon / Q000737:chemistry; D002413:Cations, Divalent; D018360:Crystallography, X-Ray; D004563:Electrochemistry; D007191:Indazoles / Q000737:chemistry*; D007536:Isomerism; D008024:Ligands; D008968:Molecular Conformation; D009584:Nitrogen / Q000737:chemistry; D009942:Organometallic Compounds / Q000138:chemical synthesis*; D012428:Ruthenium / Q000737:chemistry*; D013057:Spectrum Analysis
D000097:Acetonitriles; D000970:Antineoplastic Agents; D002413:Cations, Divalent; D007191:Indazoles; D008024:Ligands; D009942:Organometallic Compounds; C038741:dichlorotetrakis(dimethyl sulfoxide)ruthenium II; D002244:Carbon; D012428:Ruthenium; D009584:Nitrogen; C032159:acetonitrile