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Reaction of bis( p -tolyl-propargyl)-tosylamide with [(cod)RhCl] 2 in the presence of CO gives the cyclopentadienone complex [(Cpd’)Rh(CO)Cl] n (Cpd’ = TsN(CH 2 ) 2 C 4 (Tol) 2 CO). Its dissolution in DMSO or pyridine leads to decarbonylation and formation of the adducts (Cpd’)Rh(DMSO) 2 Cl and (Cpd’)Rh(Py) 2 Cl. The reaction of [(Cpd’)Rh(CO)Cl] n with AgPF 6 and p -xylene produces the sandwich arene complex [(Cpd’)Rh( p -xylene)]PF 6 , in which the arene can be substituted by t BuNC ligand to give [(Cpd’)Rh( t BuNC) 3 ]PF 6 . The arene complex acts as an efficient catalyst for the reductive amination of carbonyl compounds in the presence of CO as deoxygenation agent, producing various amines in 75–85% yields. [ABSTRACT FROM AUTHOR]

[RhCl(NCO)(nbyl)(PR3)] (nbyl = σ-norbornenyl; NCO = quinoline-8-acyl; R = p-F-C6H4) (1) has been synthesized by the reaction of [Rh(nbd)Cl]2 (nbd = norbornadiene) with 2 equivalents of NCHO (quinoline-8-carbaldehyde) and 2 equivalents of PR3. Compound 1 has been fully characterized in solution and also in the solid state by X-ray diffraction. Compound 1 shows low stability in solution and undergoes slow ring closure isomerization to [RhCl(NCO)(ntyl)(PR3)] (ntyl = σ-nortricyclyl) (2) after 12 hours. Reaction of 1 with an extra equivalent of aldehyde (NCHO) and PR3 led to the formation of [RhCl(H)(NCO)(PR3)2] (3) and an equivalent of ketone, which is a hydroacylation product. The catalytic activity of 3 in the hydroacylation of nbd with NCHO is reported as well as the catalytic activity of compound 1. Compounds 1 and 3 are proposed as intermediate species in the catalytic hydroacylation of norbornadiene with NCHO. [ABSTRACT FROM AUTHOR]

Three rhodium(I) complexes of the types [Rh( COE)Cl(η2-L)] ( 1a, 1b) and [ RhCl(η2-L) (η1-L)] ( 1c), where L = P~N donor ligands 2-[2-(diphenylphosphino) ethyl]pyridine, ( PPh2Etpy) ( a), 2-(diphenylphosphino)pyridine ( PPh2py) ( b), and 3-(diphenylphosphino)-1-propylamine (PPh2(CH2)3NH2) ( c), have been synthesized by reacting [Rh(coe)2Cl]2 with the respective ligands in 1:2 molar ratio for 1a, 1b and 1:4 molar ratio for 1c in DCM under refluxing condition. The complexes were characterized using different analytical techniques such as FT-IR, ESI(+) mass spectrometry, 1H and 31P{ 1H} NMR spectrometry, conductivity measurements, and melting point determination. The synthesized complexes were found to exhibit good catalytic activity for the transfer hydrogenation of carbonyl compounds to corresponding alcohols with high conversion rate. [ABSTRACT FROM AUTHOR]

Catalytic intramolecular hydrofunctionalization of allylphenols to heterocyclic compounds mediated by rhodium(iii) porphyrin complexes was described. The Wacker-type intermediate β-heterocyclic alkyl rhodium complex was independently synthesized and crystallized. [ABSTRACT FROM AUTHOR]

Highlights: [•] Synthesis of Rh(I) and Ir(I) carbonyl complexes of tetradentate phosphine ligand. [•] Spectroscopic and X-ray structural characterization of the synthesized complexes. [•] Catalytic activity of the complexes towards the hydroformylation of alkenes. [ABSTRACT FROM AUTHOR]

Condensation of homochiral primary amines with 1-methyl-1H-imidazole-2-carbaldehyde affords the corresponding imidazolyl-imine compounds (L1–L3) which have been employed as ligands for the preparation of half-sandwich rhodium and iridium complexes of the formula [(η5-C5Me5)MClLn][SbF6]. Treatment of these chloride compounds with AgSbF6 renders dicationic aqua-complexes [(η5-C5Me5)MLn(H2O)] [SbF6]2 which act as catalysts for the Diels–Alder reaction between methacrolein and cyclopentadiene. Catalysis occurs with good exo : endo selectivity and poor enantioselectivity. All the compounds have been completely characterized by analytical and spectroscopic methods. Characterization includes the molecular structure determination of the complexes [(η5-C5Me5)MClLn][SbF6] (Ln = L1, M = Rh, (1) Ir (4); Ln = L3, M = Ir (6)) and [(η5-C5Me5)ML1(H2O)][SbF6]2 (M = Rh (7), Ir (10)) using X-ray diffraction. From the stereochemical properties of the organometallic precursors the catalytic outcome is discussed. [ABSTRACT FROM AUTHOR]

[Rh(P2N2)X] complexes (2-X, X = Cl, BF4) featuring a tetradentate iminophosphorane phosphine ligand were synthesised and characterised. X-Ray analysis provides evidence for a square planar geometry without coordination of the chloride anion. These complexes proved to be air-sensitive, and their oxidation to Rh(iii) complexes 3-X was observed in air. The controlled reaction of 2-BF4 with one equivalent of hexachloroethane yielded [Rh(P2N2)Cl2(BF4)] (3-BF4). Direct synthesis of 3-Cl can also be achieved by coordination of the [P2N2] ligand to [RhCl(THT)3] (THT = tetrahydrothiophene). The reactivity of Rh(i) complexes 2 was further investigated, and no reaction was observed with silanes, aryl halides, or pinacolborane, although decomposition was observed under 1 atm of H2 upon prolonged heating. Interestingly, reduction of complex 3-Cl was observed by NMR upon treatment with silanes or sodium isopropoxide. Therefore, complex 3-Cl was used for catalytic transfer hydrogenation of polar bonds. The reduction of aromatic and aliphatic ketones can be carried out using 1% catalyst and 10% sodium isopropoxide, while imines are partially reduced under these conditions. [ABSTRACT FROM AUTHOR]