Gold(I)-diphenylphosphinomethane–arylazoimidazole: synthesis and multinuclear NMR investigation

Reaction of [Au₂(dppm)Cl₂] with AgOTf in CH₂Cl₂ medium followed ligand addition and leads to [Au₂(dppm)(RaaiR′)](OTf) [RaaiR′ = p-R–C₆H₄–N = N–C₃H₂–NN–1–R′, (1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (1), CH₂CH₃ (2), CH₂Ph (3), OSO₂CF₃ is the triflate anion, and dppm is the diphenylphosphinomethane-ring]. The ¹H-n.m.r. spectral measurements suggest methylene, –CH₂–, in RaaiEt gives a complex AB type multiplet while in RaaiCH₂Ph it shows AB type quartets with coupling constant of avg. 6 Hz. Considering all the moities there are a lot of different carbon atoms in the molecule which gives a lot of different peaks in the ¹³C-n.m.r spectrum. In the ¹H–¹H-COSY spectrum of the present complexes and contour peaks in the ¹H–¹³C-HMQC spectrum in the present complexes, assign the solution structure and stereoretentive transformation in each step.     

A novel series of nickel(II)-dppe-arylazoimidazole complexes. Synthesis and spectroscopic characterization

Reaction of [Ni(dppe)Cl₂/Br₂] with AgOTf in CH₂Cl₂ medium following ligand addition leads to [Ni(dppe)(OSO₂CF₃)₂] and then [Ni(dppe)(RaaiR)](OSO₂CF₃)₂ [RaaiR′ = p–R–C₆H₄–N=N–C₃H₂–NN-1–R′,(1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (1), CH₂CH₃ (2), CH₂Ph (3), OSO₂CF₃ is the triflate anion]. ³¹P{¹H}-NMR confirm that stable bis-chelated square planar Ni(II) azoimine–dppe complex formation with one sharp peaks. The ¹H NMR spectral measurements suggest azoimine link is present with lot of phenyl protons in the aromatic region. Considering all the moities there are a lot of different carbon atoms in the molecule which gives many different peaks in the ¹³C(¹H)-NMR spectrum. In the ¹H-¹H COSY spectrum in the present complexes and contour peaks in the ¹H-¹³C-HMQC spectrum in the present complexes, assign the solution structure and stereoretentive conformation in each complexes.     

Synthesis and multinuclear NMR investigation on gold(III)-triphenylphosphine-pentafluorophenyl-arylazoimidazole

Reaction of [Au(C₆F₅)(PPh₃)(OSO₂CF₃)₂] with RaaiR′ in dichloromethane medium followed ligand addition leads to [Au(PPh₃)(C₆F₅)(RaaiR′)](OSO₂CF₃)₂ where RaaiR′ = p-R-C₆H₄-N=N-C₃H₂-NN-1-R′ (I–III), abbreviated as N, N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (I), CH₂CH₃ (II), CH₂Ph (III), PPh₃ is triphenylphosphine, OSO₂CF₃ is the triflate anion. The maximum molecular peak of the corresponding molecule is observed in the ESI mass spectrum. IR spectra of the complexes show -C=N- and -N=N- stretching near at ∼1590 and 1370 cm⁻¹ and at ∼1100, 755, 695, 545, and 505 cm⁻¹ due to the presence of triphenylphosphine and pentafluoropheny ring. The ¹H NMR spectral measurements suggest methylene (-CH₂-) in RaaiEt that gives a complex AB type multiplet with coupling constant of av. 6.6 Hz while in RaaiCH₂Ph it shows AB type quartets with coupling constant of av. 6.2 Hz. Considering all the moitie there are a lot of different carbon atoms in the molecule which gives a lot of eleven different peaks in the ¹³C {¹H}NMR spectrum. In the ¹H-¹H COSY NMR spectrum of the present complexes and contour peaks in the ¹H-¹³C HMQC NMR spectrum in the present complexes, assign the solution structure and stereo-retentive transformation in each step. The article is published in the original.     

Palladium(II)-dppe-arylazoimidazole complexes: Synthesis,and spectroscopic characterization

Reaction of [Pd(dppe)Cl₂/Br₂] with AgOTf in a dichloromethane medium followed by ligand addition led to [Pd(dppe)(OSO₂CF₃)₂] and then [Pd(dppe)(RaaiR)](OSO₂CF₃)₂ [RaaiR′ = p-R-C₆H₄-N=N-C₃H₂-NN-1-R′, (1–3), abbreviated as a N,N′-chelator, where N(imidazole) and N(azo) are represented by N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (1), CH₂CH₃ (2), CH₂Ph (3), OSO₂CF₃ is the triflate anion, dppe = 1,2-bis-(diphenylphosphinoethane)]. ³¹P “¹H” NMR confirmed that due to the two phosphorus atom interaction in the azoimine symmetrical environment one sharp peak was formed. The ¹H NMR spectral measurements suggest that azo-imine link with lot of phenyl protons in the aromatic region. ¹³C (¹H) NMR spectrum, ¹H, ¹H COSY and ¹H, ¹³C HMQC spectrum assign the solution structure and stereo-retentive conformation in each complex.     

Multinuclear NMR investigation on organometallic gold(III) pentafluorophenylarylazoimidazole complexes

Reaction of [Au(C₆F₅)(tht)₂Cl](OTf) with RaaiR′ in CH₂Cl₂ medium leads to [Au(C₆F₅)(RaaiR′)Cl](OTf) [RaaiR′ = p-R–C₆H₄–N=N–C₃H₂–NN-1-R′, (1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (1), CH₂CH₃ (2), CH₂Ph (3), tht is tetrahydrothiophen]. The maximum molecular peak of [Au(C₆F₅)(MeaaiMe)Cl] is observed at m/z 599.51 (100 %) in the FAB mass spectrum. Ir spectra of the complexes show –C=N– and –N=N– stretching near at 1590 and 1370 cm⁻¹ and near at 1510, 955, 800 cm⁻¹ due to the presence of pentafluorophenyl ring. The ¹H-NMR spectral measurements suggest methylene, –CH₂–, in RaaiEt gives a complex AB type multiplet while in RaaiCH₂Ph shows AB type quartets. ¹³C-NMR spectrum of complexes confirm the molecular skeleton. In the ¹H-¹H-COSY spectrum as well as contour peaks in the ¹H-¹³C HMQC spectrum for the present complexes, assign the solution structure and stereoretentive conformation. The electrochemistry gives the ligand reduction peaks.     

Organometallic gold(I)–nickel(II)–aryldiethynyl (–C≡C(Ar)C≡C–) phosphine complexes: synthesis and multinuclear n.m.r. study

Silver triflate [AgOTf] assisted de-bromination gives [Ni(dppm/dppe/(PPh₃)₂)(OTf)₂], which on reaction with aryldiethynyls and gold(I) phosphines in CH₂Cl₂ medium, by the self assembly technique, leads to [{Ni(dppm/dppe/(PPh₃)₂}{(1,4-AB)Au(PPh₃)}₂] [{Ni₄(dppm/dppe/(PPh₃)₂)₄(1,4AB)₄}] [dppm/dppe = diphenyl phosphino-methane (1), -ethane (2), where OSO₂CF₃ is the triflate anion]. The maximum molecular peak of the corresponding molecule is observed in the ESI mass spectrum. I.r. spectra of the complexes show –C=C– and –C=N–, as well as phosphine stretching. The ¹H-n.m.r. spectra as well as ³¹P(¹H)-n.m.r. suggest solution stereochemistry, proton movement, phosphorus proton interaction. Considering all the moities there are a lot of carbon atoms in the molecule reflected by the ¹³C-n.m.r. spectrum. In the ¹H–¹H-COSY spectrum of the present complexes and contour peaks in the ¹H–¹³C-HMQC spectrum, assign the solution structure and stereo-retentive transformation in each step.     

Nickel(II)-dppa-arylazoimidazole complexes: Synthesis and detailed spectroscopic study

The reaction of [Ni(dppa)(Cl)₂] or [Ni(dppa)(Br)₂] with AgOTf gives [Ni(dppa)(OTf)₂], which then form [Ni(dppa)(RaaiR)](OSO₂CF₃)₂ under the action of arylazoimidazole(RaaiR) in a dichloromethane medium [RaaiR′ = p-R-C₆H₄-N=N-C₃H₂-NN-1-R′, (I–III), abbreviated as N,N′-chelating agent, where N(imidazole) and N(azo) represent N and N’, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (I), CH₂CH₃ (II), CH₂Ph (III), OSO₂CF₃ is the triflate anion]. The ¹H NMR spectral measurements suggest that a bound azoimine is responsible for a number of signals of phenyl protons in the aromatic region. The molecules of the complexes contain a number of different carbon atoms which gives a number of different peaks in the ¹³C (¹H) NMR spectrum. The text was submitted by the author in English. The text was submitted by the author in English.     

Gold(I)-Gold(III)-4,4′-bpy-phosphine complexes: Synthesis and multinuclear NMR study

Silver assisted de-bromination gives [Au₂(dppm/dppe/dppa) (OTf)₂], which on reaction with 4,4′-bpy and gold(I) phosphines in CH₂Cl₂ medium, by the self assembly technique, leads to [(PPh₃)Au(4,4′-bpy)Au(PPh₃)], (1a–1d,2), [{Au₂(dppm/dppe/dppa)}{(4,4-bpy)Au(PPh₃)}₂](NO₃)₄, (3), [{Au₄(dppm/dppe/dppa)₂(4,4-bpy)₂}](OTf)_4, (4), [{(PPh₃)Au^I(4,4′-bpy)}₂Au^III(C₆F₅/Mes)](NO₃)₃, (5) [dppm/dppe/dppa =diphenyl phosphino-methane(a), –ethane(b), ammine(c), C₆F₅/Mes pentafluorophenyl/mesitylene]. The maximum molecular peak of the corresponding molecule is observed in the ESI mass spectrum. Ir spectra of the complexes show –C=C–, –C=N–, as well as phosphine, mesitylene and pentafluorophenyl stretching. The ¹H-NMR spectra as well as ³¹P(¹H)-NMR suggest solution stereochemistry, proton movement and phosphorus proton interaction. Considering all the moities there are a lot of carbon atoms in the molecule reflected by the ¹³C(H)-NMR spectrum. In the ¹H–¹H COSY spectrum of the present complexes and contour peaks in the ¹H–¹³C-HMQC spectrum, assign the solution structure and stereoretentive transformation in each step.     

Gold(I)-triphenylphosphine-arylazoimidazole: Synthesis and spectral (H,C, COSY,HMQC NMR) characterization

The reaction of [Au(OSO₂CF₃)(PPh₃)] with arylazoimidazole in dichloromethane followed by NH₄PF₆ leads to [Au(RAaiR′)(PPh₃)]PF₆ (RAaiR′ = p-R-N=N-C₃H₂-NN-1-R′), abbreviated as N,N′/-chelator, where N (imidazole) and N (azo) represent N and N′, respectively; R = H (a), Me (b), Cl (c), and R′ = Me (I), CH₂CH₃ (II), CH₂Ph (III)]. IR spectra of the complexes show -C=H- and -N=N-stretchings at 1590 and 1370 and at 1100, 755, 695, 545, and 505 cm⁻¹ due to the presence of the triphenylphosphine ring. The ¹H NMR spectral measurements suggest that methylene (-CH₂-) in (RAai)Et gives a complex of the AB type multiplet with a coupling constant of ∼7.6 Hz while in RAaiCH₂Ph it shows AB type quartets with coupling constant of av. 7.2 Hz. Considering the arylazoimidazole moity, there are different carbon atoms in the molecule giving different peaks in the ¹³C NMR spectrum of the complexes. In the ¹H-¹H COSY spectrum of the present complexes, the absence of any off-diagonal peaks extending from δ = 14.12 and 9.55 ppm confirms their assignment of no proton on N(1) and N(3), respectively. Contour peaks in the ¹H-¹³C HMQC spectrum in the present complexes, the absence of any contours at δ = 157.12, 160.76, 155.67, and 157.68–160.2 ppm assign them to the C(2), C(6), C(12), and C(PPh₃) carbon atoms, respectively. The solution structure and stereoretentive transformation in each step have been established from the ¹H NMR results. The article was submitted by the authors in English.     

Gold(III)pentafluorophenylarylazoimidazole: Synthesis and spectral (H, C, COSY, HMQC NMR) characterisation

Reaction of [Au^III(C₆F₅)₃(tht)] with RaaiR′ in dichloromethane medium leads to [Au^III(C₆F₅)₃ (RaaiR′)] [RaaiR′=p-R-C₆H₄-N=N-C₃H₂-NN-l-R′, (1-3), R = H (a), Me (b), Cl (c) and R′= Me (1), CH₂CH₃ (2), CH₂Ph (3), tht is tetrahydrothiophen]. The nine new complexes are characterised by ES/MS as well as FAB, IR and multinuclear NMR (¹H,¹³C,¹⁹F) spectroscopic studies. In addition to dimensional NMR studies as¹H,¹H COSY and¹H¹³C HMQC permit complete assignment of the complexes in the solution phase.     

Synthesis,Spectra and Electrochemistry of Dinitro-bis-{1-alkyl-2-(arylazo) imidazole} Ruthenium(II). Nitro-nitroso Derivatives and Reactivity of the Electrophilic {Ru-NO}<Superscript>6</Superscript>System

Ag⁺ assisted aquation of blue cis-trans-cis-RuCl₂(RaaiR′)₂ (4–6) leads to the synthesis of solvento species, blue-violet cis-trans-cis-[Ru(OH₂)₂(RaaiR′)₂](ClO₄)₂ [Raai R′=p-R-C₆H₄ N=N–C₃H₂–NN–1–R′, (1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), OMe (b), NO₂ (c) and R′ = Me (1/4/7/10), CH₂CH₃ (2/5/8/11), CH₂Ph (3/6/9/12)] that have been reacted with NO₂⁻in warm EtOH resulting in violet dinitro complexes of the type, Ru(NO₂)₂(RaaiR′)₂ (7–9). The nitrite complexes are useful synthons of electrophilic nitrosyls, and on triturating the compounds, (7b–9b) with conc. HClO₄ nitro-nitrosyl derivatives, [Ru(NO₂)(NO)(OMeaaiR′)₂](ClO₄)₂ (10b–12b) are isolated. The solution structure and stereoretentive transformation in each step have been established from ¹H n.m.r. results. All the complexes exhibit strong MLCT transitions in the visible region. They are redox active and display one metal-centred oxidation and successive ligand-based reductions. The redox potentials of Ru(III)/Ru(II) (E_1/2^M) of (10b–12b) are anodically shifted by ∼ ∼0.2 V as compared to those of dinitro precursors, (7b–9b). The ν(NO) >1900 cm⁻¹ strongly suggests the presence of linear Ru–NO bonding. The electrophilic behaviour of metal bound nitrosyl has been proved in one case (12b) by reacting with a bicyclic ketone, camphor, containing an active methylene group and an arylhydrazone with an active methine group, and the heteroleptic tris chelates thus formed have been characterised.     

Organometallic gold(I)-pentafluorophenyl-P,O, As,S, TPA,dppm, dppe,dppa-coordinating-phosphines: synthesis and detailed spectroscopic characterisation

[Au(C₆F₅)(tht)], which on reaction with P, O, S-coordinating phosphines in CH₂Cl₂ medium leads to [Au(C₆F₅)(X)] [X = PPh₃ H, (1a), oMe, (1b), pMe, (1c), mMe, (1d), AsPh₃ (2), OPPh₃ (3), SPPh₃ (4), dppm, dppe, dppa = diphenylphosphino-methane,-ethane,-ammine(5, 6, 7), TPA = 135-tetraaza-7-phosphino adamentane(8), Py4H (9a), 4Bu (9b), 4Ac (9c), tht = tetrahydrothiophen, C₆F₅ is the pentafluorophenyl ring]. The maximum molecular peak of the corresponding molecule is observed in the ESI mass spectrum. I.r. spectra of the complexes show –C = C– and C₆F₅ stretching near at 1610 and 1510, 955, 800 cm⁻¹. The ¹H-n.m.r. spectra as well as ³¹P- (¹H)n.m.r. suggest solution stereochemistry, proton movement, phosphorus proton interaction. ¹³C-n.m.r. spectrum reflect the carbon skeleton in the molecule. In the ¹H–¹H COSY spectrum of the present complexes and contour peaks in the ¹H–¹³C-HMQC spectrum, assign the solution structure and stereoretentive conformation in each step.     

Ruthenium(II)-arylazoimidazole-8-hydroxyquinolinate complexes: Synthesis,spectral study (H,C, COSY,HMQC-NMR) and redox properties

The reaction of [Ru(OH₂)₂(RaaiR′)₂]²⁺ (RaaiR′ = 1-alkyl-2-(arylazo)imidazole, p-R-C₆H₄-N=N-C₃H₂NN(1)-R′, R = H (1), Me (2), Cl (3); R′ = Me (a), Et (b), CH₂Ph (c)) with 8-quinolinol (HQ) in acetone solution followed by the addition of NH₄PF₆ has afforded violet coloured mixed ligand complexes of the composition [Ru(Q)(RaaiR′)₂](PF₆). The maximum molecular peak of 1b is observed at m’z 790 (50%) in the ESI mass spectrum. Ir spectra of the complexes show -C=N- and -N=N- stretching near at 1590 and 1370 cm⁻¹. The ¹H NMR spectral measurements suggest methylene, -CH₂−, in RaaiEt gives a complex AB type while in RaaiCH₂Ph it shows AB type quartets. Considering the arylazoimidazole and oxine moitie there are twenty different carbon atoms in the molecule which gives a total of twenty different peaks in the C¹³ NMR spectrum of complex 1a. In the ¹H-¹H COSY spectrum of the present complexes, absence of any off-diagonal peaks extending from δ = 14.12 and 9.55 ppm confirm their assignment of no proton on N(1) and N(3) respectively. Contour peaks in the ¹H-¹³C HMQC spectrum in the present complexes, the absence of any contours at δ = 157.12, 160.76, 155.67 ppm and 157.68–160.2 ppm assign them to the C(2), C(6), C(g) and C(h), C(i) carbon atoms respectively. The solution structure and stereoretentive transformation in each step have been established from n.m.r. results. Cyclic voltammograme show a Ru(III)/Ru(II) couple at 1.0–1.1 V versus SCE along with three successive ligand reductions.     

Ruthenium-mediated Selective Aromatic Thiolation in the Complex [RuII{o-S—C6H4-(p-R-)—N=N—C3H2NN(1)—R′}2]. Synthesis, Spectroscopic, e.p.r., Electro-chemical Characterization and Spectro-electrochemical Correlation

The reaction of ctc-[Ru(RaaiR′)₂Cl₂] (3a–3i) [RaaiR′=1-alkyl-2-(arylazo)imidazole, p-R—C₆H₄—N=N— C₃H₂NN(1)—R′, R=H, OMe, NO₂, R′=Me, Et, Bz] with KS₂COR′′ (R′′=Me, Et, Pr, Bu or CH₂Ph) in boiling dimethylformamide afforded [Ru^II{o-S—C₆H₄(p-R-)—N=N—C₃H₂NN(1)—R′}₂] (4a–4i), where the ortho-carbon atom of the pendant phenyl ring of both ligands has been selectively and directedly thiolated. The newly formed tridentate thiolate ligands are bound in a meridional fashion. The solution electronic spectra exhibit a strong MLCT band near 700 nm and near 550 nm, respectively in DCM. The molecular geometry of the complexes in solution has been determined by H n.m.r. spectroscopy. Cyclic voltammograms show a Ru(II)/Ru(III) couple near 0.4 V and an irreversible oxidation response near 1.0 V due to oxidation of the coordinated thiol group, along with two successive reversible ligand reductions in the range −0.80–0.87 V (one electron), −1.38–1.42 V (one electron). Coulometric oxidation of the complexes at 0.6 V versus SCE in CH₂Cl₂ produced an unstable Ru(III) congener. When R=Me the presence of trivalent ruthenium was proved by a rhombic e.p.r. spectrum having g₁=2.349, g₂=2.310.     

Synthesis, spectral and electrochemical behaviour of cytosinato bridged complexes of ruthenium(II) and platinum(II) with 1-alkyl-2-(arylazo)imidazoles

Dechlorination of M(RaaiR′) _n Cl₂ by AgNO₃ produced [M(RaaiR′) _n (MeCN)₂]⁺² [M = Ru(II), n = 2; Pt(II), n = 1; RaaiR′ = 1-alkyl-2-(arylazo)imidazole)] which upon reaction with the nucleobase cytosine (C) in MeCN solution gave cytosinato bridged dimeric compounds which were isolated as perchlorate salts [M₂(RaaiR′) _n (C)₂](ClO₄)₂ · H₂O. The products were characterized by IR, u.v.–vis., ¹H-n.m.r. spectroscopy and cyclic voltammetry. In MeCN solution the ruthenium complexes exhibit a strong MLCT band at 550–555 nm and two redox couples positive to SCE due to two metal-center oxidation along with ligand reduction, negative to SCE. The platinum complexes show a weak transition at 500–520 nm in MeCN and exhibit only ligand reduction in cyclic voltammetry. The coordination of the ligand was supported by ¹H-n.m.r. spectral data.     

Kinetic and mechanistic studies of the interaction of 2-mercapto pyridine with dichloro[1-alkyl-2-(arylazo)imidazole]palladium(II) complexes

Nucleophilic substitution of Pd(RaaiR′)Cl₂ [(RaaiR′ = 1-alkyl-2-(arylazo)imidazole, p-R-C₆H₄-N=N-C₃H₂NN-1-R′; where R = H(a)/ Me(b)/ Cl(c) and R′ = Et(1)/Bz(2)] with 2-Mercaptopyridine (2-SH-Py) in acetonitrile (MeCN) at 298 K, to form [Pd₂(2-S-Py)₄], has been studied spectrophotometrically under pseudo-first-order conditions and the analyses support the nucleophilic association path. The reaction follows the rate law, Rate = {k ₀ + k [2-SH-Py] ₀ ² }[Pd(RaaiR′)Cl₂]: first order in Pd(RaaiR′)Cl₂ and second order in 2-SH-Py. The rate of the reaction follows the order: Pd(RaaiEt)Cl₂ (1) < Pd(RaaiBz)Cl₂ (2) and Pd(MeaaiR′)Cl₂ (b) < Pd(HaaiR′)Cl₂ (a) < Pd(ClaaiR′)Cl₂ (c). External addition of Cl⁻ (LiCl) and HCl suppresses the rate (Rate ∝ 1/[Cl⁻]₀ & ∝1/[HCl]₀). The reactions have been studied at different temperatures (293–308 K) and activation parameters (Δ^‡ H° and Δ ^‡ S°) of the reactions were calculated from the Eyring plot and support the proposed mechanism.     

Syntheses,characterization, and crystal structures of ruthenium(II)/(III) complexes with tridentate salicylaldiminato ligands

Treatment of [Ru(PPh₃)₃Cl₂] with one equivalent of tridentate Schiff base 2-[(2-dimethylamino-ethylimino)-methyl]-phenol (HL) in the presence of triethylamine afforded a ruthenium(III) complex [RuCl₃(κ²-N,N-NH₂CH₂CH₂NMe₂)(PPh₃)] as a result of decomposition of HL. Interaction of HL and one equivalent of [RuHCl(CO)(PPh₃)₃], [Ru(CO)₂Cl₂] or [Ru(tht)₄Cl₂] (tht = tetrahydrothiophene) under different conditions led to isolation of the corresponding ruthenium(II) complexes [RuCl(κ³-N,N,O-L)(CO)(PPh₃)] (2), [RuCl(κ³-N,N,O-L)(CO)₂] (3), and a ruthenium(III) complex [RuCl₂(κ³-N,N,O-L)(tht)] (4), respectively. Molecular structures of 1·CH₂Cl₂, 2·CH₂Cl₂, 3 and 4 have been determined by single-crystal X-ray diffraction.     

Oxygen- versus carbon-coordination of the alpha-stabilized phosphorus ylide Ph<Subscript>3</Subscript>P=C(H)R in palladacycles bearing secondary amines

The ortho-metalated complex [Pd(x){κ ² (C,N)-[C₆H₄CH₂NRR′ (Y)}] (2a–4a and 2b–3b) was prepared by refluxing in benzene equimolecular amounts of Pd(OAc)₂ and secondary benzylamine [a, EtNHCH₂Ph; b, t-BuNHCH₂Ph followed by addition of excess NaCl. The reaction of the complexes [Pd(x){κ ² (C,N)-[C₆H₄CH₂NRR′ (Y)}] (2a–4a and 2b–3b) with a stoichiometric amount of Ph₃P=C(H)COC₆H₄-4-Z (Z = Br, Ph) (ZBPPY) (1:1 molar ratio), in THF at low temperature, gives the cationic derivatives [Pd(OC(Z-4-C₆H₄C=CHPPh₃){κ ² (C,N)-[C₆H₄CH₂NRR′(Y)}] (5a–9a, 4b–6b, and 4b′–6b′), in which the ylide ligand is O-coordinated to the Pd(II) center and trans to the ortho-metalated C(6)H(4) group, in an “end-on carbonyl”. Ortho-metallation, ylide O-coordination, and C-coordination in complexes (5a–9a, 4b–6b, and 4b′–6b′) were characterized by elemental analysis as well as various spectroscopic techniques.     

Mononuclear and heterobimetallic palladium(II) and platinum(II) complexes containing the mixed ligands <Emphasis Type="Italic">N</Emphasis>-(2-pyridyl or 2-pyrimidyl) acetamide and tertiary diphosphine

Palladium(II) and platinum(II) complexes containing mixed ligands N-(2-pyridyl)acetamide (AH) or N-(2-pyrimidyl)acetamide (BH) and the diphosphines Ph₂P(CH₂) _n PPh₂, (n = 1, 2 or 3) have been prepared. The prepared complexes [Pd(A)₂(diphos)] or [Pd(B)₂(diphos)] have been used effectively to prepare bimetallic complexes of the type [(diphos)Pd(μ-L)₂M′Cl₂] where M′ = Co, Cu, Mn, Ni, Pd, Pt or SnCl₂; L = A or B. The prepared complexes were characterized by elemental analysis magnetic susceptibility, i.r. and UV–Vis spectral data. ³¹P–{¹H}-n.m.r. data have been applied to characterize the produced linkage isomers.     

Linked Metal-cluster Systems: Isolation and Characterisation of {anti-[(p-cymene)RuCl]-μ-[κ2-P,P′;κ1-P′′-(PPh2CH2)3CMe]-[AuPt3(CO)3(PCy3)3]}(PF6)2

The new mixed-metal complex {anti-[(p-cymene)RuCl]-μ-[κ ²-P,P′;κ ¹-P′′-(PPh₂CH₂)₃CMe]-[AuCl]}PF₆ and its cluster derivative {anti-[(p-cymene)RuCl]-μ-[κ ²-P,P′;κ ¹-P′′-(PPh₂CH₂)₃CMe]-[AuPt₃(CO)₃(PCy₃)₃]}(PF₆)₂ have been prepared and characterized. Notably, NMR spectroscopy and high resolution FT-ICR mass spectrometry, including a tandem mass spectrometric analysis, demonstrated the formation of these compounds that was also confirmed by single crystal X-ray diffraction analysis.