Interaction of [RuCl2(PR3)3] (R = Ph, p-tolyl) with some Rh(III), Ir(III) and Pt(IV) tertiary phosphine complexes

Reactions of RuCl₂(PR₃)₃ [PR₃ = PPh₃ or P(p-tolyl)₃ with several monomeric phosphine complexes of rhodium(III), iridium(III) and platinum(IV) have been studied. The reactions with mer-MCl₃(P′R₃)₃ (M = Rh, P′R₃ = PEt₂Ph, PMe₂Ph, PMe₂Ph; M = Ir, P′R₃ = PBuPh₂, PMePh₂, PEt₂Ph) involves a phosphine ligand transfer between metal atoms to afford novel dark coloured heterobimetallic complexes containing a triple chloro-bridge. The reactions of RuCl₂(PR₃)₃ with PtCl₄(P′R₃)₂ (P′R₃ = PEt₂Ph, PBu₂Ph), however, do not give evidence for the formation of dinuclear complexes containing the (RuCl₃Pt) unit, but a reduction of Pt^IV to Pt^II occurs with transfer of phosphine ligands between the two metals. The formulation of these complexes has been established by ³¹P NMR spectroscopy.     

Reactions of the complexes [Re2(CO)9(η-P-P)] (P-P=Ph2P(CH2)nPPh2, n=1-6) with Me3NO: formation of close-bridged complexes [Re2(CO)8(μ-P-P)] and phosphine oxide complexes [Re2(CO)9{P-P(O)}]

Reactions of [Re₂(CO)₁₀] with Me₃NO and diphosphines [Ph₂P(CH₂)_nPPh₂, n=1-6] yield mixtures of the monodentate-coordinated diphosphine complexes [Re₂(CO)₉(η¹-P-P)] (P-P=Ph₂P(CH₂)_nPPh₂, n=1-6) (yields 5-40%) and bridged dimers [{Re₂(CO)₉}₂(μ-P-P)] (5-50%). These complexes were isolated as either equatorial or axial isomers, or a mixture of two isomers. Reactions of the monodentate complexes with Me₃NO yield close-bridged complexes [Re₂(CO)₈(μ-P-P)] and phosphine oxide complexes [Re₂(CO)₉{P-P(O)}]. The structures of the close-bridged complexes 1 (n=3) and 2 (n=4), were determined by X-ray crystallography. The Re-Re bond in the close-bridged complex with the longest phosphine chain (n=6) is readily cleaved in CDCl₃ to give the complex [{cis-ReCl(CO)₄}₂(μ-dpph)] (3) as the product, the structure of which was also determined by X-ray crystallography.     

Regiospecific C(naphthyl)-H bond activation: Isolation and characterization of cyclopalladates

In ethanol medium disodium tetrachloropalladate selectively activates the C8-H bond of naphthyl group present in 1-(2′-hydroxy-5′-methylphenylazo)naphthalene(H₂L¹) at room temperature and produces cyclometallate [PdL¹(PPh₃)] in presence of triphenylphosphine. Under similar reaction condition, the C(naphthyl)-H bond activation of 1-(2′-methoxy-5′-methylphenylazo)naphthalene (HL²) occurs at C2 and cyclopalladate [PdL²Cl] has been isolated as product. The labile nature of the Pd ←:O(R) bond of [PdL²Cl] in solution is established from the electronic and NMR spectra. Cyclopalladate [PdL²Cl] reacts with thallium(I) cyclopentadienide and yields [PdL²(Cp)], where both σ- and π-palladium(II)-carbon bonds exist. All the cyclopalladates have been isolated in pure form and characterized on the basis of their spectral data. The molecular structure of cyclopalladate [PdL¹(PPh₃)] has been determined by single crystal X-ray diffraction method. In [PdL¹(PPh₃)], the metal ion is bonded to C8 (peri-position of 1-azonaphthyl fagment), N1 of diazene function, O1 of phenolic group and P1 of triphenylphosphine. The tetra-coordination around palladium(II) is in a distorted square-planar geometry.     

Complexes of hybrid ligands. Synthesis of mixed-ligand,phosphino-alkoxide complexes of Pd2+: the crystal and molecular structure of the complex Ph2 PCH2C(CF3 )2OPdCl(PPh2Me)

The hybrid, bidentate, diarylphosphino-alkoxide ligand PPh₂CH₂C(CF₃)₂O⁻, L¹, gives the Pd²⁺ bis- complex Pd(L¹)₂, from which the chloride-bridged dinuclear complex [(L¹)Pd(μ-Cl)₂Pd(L¹)] is made by reaction with PdCl₂(PhCN)₂. Cleavage of the dinuclear complex with monodentate ligands L² then gives Pd(L¹)Cl(L²) (L² =PPh₃, PPh₂Me, PPhMe₂, PMe₃, SMe₂, or pyridine); NMR data show that PR₃ is cis to the phosphine site in L¹ in these complexes, but SMe₂ or pyridine are probably trans.A complete crystal and molecular structural determination has been made for cis-Pd(L¹)Cl(PPh₂Me). Crystals are monoclinic, space group P2₁/c, a = 10.821(1), b = 14.600(1), c = 18.674(2) Å, β = 101.25(1)°, V = 2893 ų, Z = 4. Least-squares refinement on F of 361 variables using 3977 observations converged at a conventional agreement factor R = 0.025. The complex is square-planar, with the two phosphines cis; the 5-membered chelate ring is in a dissymmetric envelope conformation. The PdP bonds differ in length, with that to the unidentate phosphine, 2.259(1) Å, being significantly longer than that to the phosphine on the chelating ligand, 2.231(1) Å.     

The coordination of small molecules by manganese(II) phosphine complexes. Part 12. The synthesis of some tetrahydrofuran/long chain tertiary phosphine complexes of manganese(II) halides,MnX2(phosphine)(THF), and their reaction with molecular oxygen

Manganese(II) complexes of long chain phosphines, MnX₂(phosphine)(THF) XCl, Br, I; phosphine=P(C₁₂H₂₅)₃, P(C₁₄H₂₉)₃, P(C₁₆H₃₃)₃, PPh(C₁₂H₂₅)₂, PPh(C₁₄H₂₉)₂, PPh(C₁₆H₃₃)₂; THF=tetrahydrofuran have been prepared and characterised. These complexes react reversibly with molecular oxygen both in the solid state and in THF and toluene solution forming 1:1 Mn:O₂ adducts. These adducts are monomeric in toluene and THF and molecular weight measurements confirm that the THF ligand remains coordinated in toluene solution leading to the formation of MnX₂(phosphine)(THF)(O₂) species. All the O₂-adducts are highly coloured and binding curves have been constructed and K_o2 values calculated. Based on these K_o2 values the affinity for dioxygen is in the order XCl>Br>I in toluene solution, with Hill coefficient, n, indicating cooperativity (1-1.5). In THF dioxygen binding does not appear to be cooperative.     

Synthesis,FT-IR and 1H NMR studies of alkali and alkaline earth metal complexes with guanosine

The synthesis of complexes of Li(I), K(I), Mg(II), Ca(II) and Ba(II) with guanosine in basic non aqueous solutions is described. The complexes were of two types: (1) complexes having the general formula, M(Guo)_nX_m·YH₂O·ZC₂H₅OH, where M = Mg(II), Ca(II), Ba(II) and Li(I), n = 1,2,4, X = Cl^?, Br^?, NO₃^?, ClO₄^? and OH^?, m = 1,2, Y = 0?6 and X = 0?2, and (2) complexes with the general formula, M(GuoH-1)(OH)_n^?1·YH₂O, where M = K(I), Ca(Il) and Ba(II), GuoH-1 =Ionized guanosine at N₁, n = 1,2 and Y = 1?3. The complexes are characterized by their proton nuclear magnetic resonance (¹H NMR) and Fourier transform infrared (FT-IR) spectra. The FT-IR and ¹H NMR data of the non ionized nucleoside complexes suggest that the metal binding is through the N₇-site of guanine and that the anion (X) is hydrogen bonded to N₁H and NH₂ groups. In the N₁-ionized guanosine complexes the metal binding is via the O₆^? of guanine. All the complexes formed exhibited a transition of the sugar conformation from C₂′-endo/anti in the free nucleoside to C₃′-endo/anti in the metal complexes.     

Cyclic and acyclic compartmental Schiff bases, their reduced analogues and related mononuclear and heterodinuclear complexes

[1+1] macrocyclic and [1+2] macroacyclic compartmental ligands (H₂L), containing one N₂O₂, N₃O₂, N₂O₃, N₄O₂ or O₂N₂O₂ Schiff base site and one O₂O_n (n=3, 4) crown-ether like site, have been prepared by self-condensation of the appropriate formyl- and amine precursors. The template procedure in the presence of sodium ion afforded Na₂(L) or Na(HL) · nH₂O. When reacted with the appropriate transition metal acetate hydrate, H₂L form M(L) · nH₂O, M(HL)(CH₃COO) · nH₂O, M(H₂L)(X)₂ · nH₂O (M=Cu²⁺, Co²⁺, Ni²⁺; X=CH₃COO⁻, Cl⁻) or Mn(L)(CH₃COO) · nH₂O according to the experimental conditions used. The same complexes have been prepared by condensation of the appropriate precursors in the presence of the desired metal ion. The Schiff bases H₂L have been reduced by NaBH₄ to the related polyamine derivatives H₂R, which form, when reacted with the appropriate metal ions, M(H₂R)(X)₂ (M= Co²⁺, Ni²⁺; X=CH₃COO⁻, Cl⁻), Cu(R) · nH₂O and Mn(R)(CH₃COO) · nH₂O. The prepared ligands and related complexes have been characterized by IR, NMR and mass spectrometry. The [1+1] cyclic nature of the macrocyclic polyamine systems and the site occupancy of sodium ion have been ascertained, at least for the sodium (I) complex with the macrocyclic ligand containing one N₃O₂ Schiff base and one O₂O₃ crown-ether like coordination chamber, by an X-ray structural determination. In this complex the asymmetric unit consists of one cyclic molecule of the ligand coordinated to a sodium ion by the five oxygen atoms of the ligand. The coordination geometry of the sodium ion can be described as a pentagonal pyramid with the metal ion occupying the vertex. In the mononuclear complexes with H₂L or H₂R the transition metal ion invariantly occupies the Schiff base site; the sodium ion, on the contrary, prefers the crown-ether like site. Accordingly, the heterodinuclear complexes [MNa(L)(CH₃COO)_x] (M=Cu²⁺, Co²⁺, Ni², x=1; M=Mn³⁺, x=2) have been synthesised by reacting the appropriate formyl and amine precursors in the presence of M(CH₃COO)_n · nH₂O and NaOH in a 1:1:1:2 molar ratio. The reaction of the mononuclear transition metal complexes with Na(CH₃COO) · nH₂O gives rise to the same heterodinuclear complexes. Similarly [MNa(R)(CH₃COO)_x] have been prepared by reaction of the appropriate polyamine ligand H₂R with the desired metal acetate hydrate and NaOH in 1:1:2 molar ratio.     

Phosphorus-31 and cadmium-113 NMR studies of some cadmium(II) complexes containing tricyclohexylphosphine and tributylphosphine

Phosphorus-31 and cadmium-113 NMR spectroscopy has been used to study the interaction between tertiary phosphines (P(c-C₆H₁₁)₃ and PBu₃) and Cd(O₃SCF₃)₂, Cd(ClO₄)₂, Cd(CF₃COO)₂ and Cd(SCN)₂ salts in solution. the NMR data imply the formation in solution of novel 1:1 adducts CdX₂(phos) (X = O₃SCF₃, ClO₄, CF₃COO, phos = P(c-C₆H₁₁)₃, PBu₃) in which there is substantial interaction between the anions and cadmium. Data are also presented for mixed phosphine complexes CdX₂[P(c-C₆H₁₁)₃][PBu₃] (X = O₃SCF₃, ClO₄, NO₃, CF₃COO, CH₃COO, Cl, Br, I, SCN). The two bond coupling constants ²J(P′P) of these mixed phosphine complexes decrease as the coordination ability of the anion increases and cover the narrow range from 95 Hz to 66 Hz.     

Synthesis and characterization of uranyl(VI) and thorium(IV) complexes with phosphine oxides. The crystal structure of UO2(NO3)2(NO2-C6H4Ph2PO)2

Uranyl(VI) and thorium(IV) complexes of the type UO₂(NO₃)₂(L¹)₂, UO₂(NO₃)₂(L²)₂, UO₂(CH₃COO)₂L¹, UO₂(CH₃COO)₂L², Th(NO₃)₄(L¹)₂ and Th(NO₃)₄(L²)₂ (L¹ = (2-nitro)phenyl-bis-phenyl phosphine oxide, L² = triferrocenylphosphine oxide) are reported, together with their physico-chemical properties.The crystal structure of UO₂(NO₃)₂(L¹)₂ is also reported. The crystals are monoclinic, space group P2₁/n with a = 17.78(1), b = 13.88(1), c = 17.37(1) Å, β = 114.8(1)° for Z = 4. The uranium atom is 8-coordinated, the uranyl(VI) group being equatorially surrounded by an irregular hexagon of six oxygen atoms from two trans neutral ligands and two nitrato groups.     

Reductive nitrosation of molybdenum and tungsten halides. III. Intramolecular redox reactions of molybdenum and tungsten halo nitrosyl complexes

Thermally initiated exothermic intramolecular redox reactions of [M(NO)₂Cl₂]_n and M(NO)₂CL₂L₂ (where M = Mo or W; L = PPh₃AsPh₃ or OPPh₃) type complexes were observed at definite temperatures. In these reactions the coordinated NO oxidizes M or L and N₂O or N₂ containing gases are formed. Thermal analysis was found to be a reliable supplementary method to differentiate between phosphine and phosphine oxide substituted halo nitrosyl complexes.     

Aerosol-assisted chemical vapour deposition (AACVD) of silver films from triorganophosphine adducts of silver carboxylates, including the structure of [Ag(O2CC3F7)(PPh3)2]

Silver carboxylates [Ag(O₂CR): R=Me, ^tBu, 2,4,6-Me₃C₆H₂], fluorocarboxlyates [Ag(O₂CR_f): R_f=C₃F₇, C₆F₁₃, C₇F₁₅] and their phosphine adducts [Ag(O₂CR)·nPR₃′: R=Me, ^tBu, 2,4,6-Me₃C₆H₂, R′=Me, Ph, n=2; R=Me, R′=Me, n=3; Ag(O₂CR_f).2PPh₃, R_f=C₃F₇, C₆F₁₃, C₇F₁₅] have been synthesised, characterised spectroscopically and used as precursors in the aerosol-assisted chemical vapour deposition of silver films. All the phosphine adducts produced films, though in general PMe₃ adducts, proved more successful than PPh₃ analogues. The fluoro-carboxylates and their PPh₃ adducts all generated silver films, though the growth rate for the adducts was lower. All these latter films showed carbon impurities while fluorine was also evident in most cases. The X-ray structure of AgO₂CC₃F₇·2PPh₃ is also reported.     

Detecting the bonding type of dithiocarbamate ligands in their complexes as inferred from the asymmetric CS mode

The IR spectra of a number of dithiocarbamate (dtc) complexes (M(R₂dtc)₂, n = 2, M = Ni, Cu, Zn, Cd, Pb, Hg, Se, Te; n = 3, M = Cr, Fe, Co, As, Sb, Bi, R = Et, Prⁿ, Prⁱ, Buⁿ, Brⁱ, as well as the laser Raman spectra of a few colourless compounds (M(Et₂dtc)₂ M = Zn, Cd, Pb, Hg), have been recorded and discussed as to the validity of the Bonati-Ugo (BU) criterion for discerning the dtc bonding type from its ν_as(CS) band (ca. 1000 cm^?1), By comparing these bands for dtc complexes containing different N-substituted ligands, their splittings can be proved to be due to interligand coupling of the CS ligand modes. Further comparison with X-ray diffraction data shows that the dtc ligands, irrespective of the host complex or the ligand bonding type, are at sites of C₁ symmetry, thus ruling out the possibility to detect the ligand bonding type from the solid state vibrational spectra. New evidence is presented that the RN modes are present in the 1000 cm^?1 region, thus making it unsuitable for the determination of the ligand bonding type.     

New chiral macrocyclic lanthanide complexes derived from (1R,2R)-1,2-diaminocyclohexane and 2,6-diformylpyridine

The new enantiopure complexes [LnL](NO₃)₃ · nH₂O (Ln = Dy⁺³, Ho⁺³, Er⁺³, Lu⁺³) and [LnL]Cl₃ · nH₂O (Ln = Nd⁺³, Sm⁺³, Gd⁺³, Tb⁺³, Dy⁺³, Ho⁺³, Er⁺³, Tm⁺³, Lu⁺³) of the chiral macrocycle L derived from (1R,2R)-1,2-diaminocyclohexane and 2,6-diformylpyridine have been synthesised. The preference of macrocycle L for the heavier lanthanide(III) ions has been established on the basis of competition reaction. The complexes have been characterised by NMR spectroscopy and mass spectrometry. ¹H NMR signals of deuterated water solutions of the Ce⁺³, Nd⁺³ and Eu⁺³ complexes have been assigned on the basis of the COSY and HMQC spectra, and for the remaining lanthanide complexes the signals were assigned on the basis of linewidths analysis. The paramagnetic shifts of the series of lanthanide complexes [LnL](NO₃)₃ · nH₂O and [LnL]Cl₃ · nH₂O have been analysed using both crystal-field dependent and independent methods in order to separate contact and dipolar contributions and establish isostructurality along the series of lanthanide complexes in solution. The data obtained for nitrate derivatives in organic solvent indicate rather irregular deviations from the plots based on those methods, while the plots obtained for water solutions show the characteristic brake in the middle of the lanthanide series, that is interpreted as a result of change of the number of axially coordinated water molecules. The apparent inconsistencies of results obtained on the basis of crystal-field independent method are discussed.     

Ruthenium(II) carbonyl complexes containing S-methylisothiosemicarbazone based tetradentate ligand: synthesis, characterization and biological applications

A series of hexa-coordinated ruthenium(II) complexes of the type [Ru(CO)(B)L ⁿ ] (n = 1–4; B = PPh₃, AsPh₃ or Py) have been synthesized by reacting dibasic quadridentate Schiff base ligands H₂L ⁿ (n = 1–4) with starting complexes [RuHCl(CO)(EPh₃)₂(B)] (E = P or As; B = PPh₃, AsPh₃ or Py). The synthesized complexes were characterized using elemental and various spectral studies including UV–Vis, FT-IR, NMR (¹H, ¹³C and ³¹P) and mass spectroscopy. An octahedral geometry was tentatively proposed for all the complexes based on the spectral data obtained. The experiments on antioxidant activity showed that the ruthenium(II) S-methylisothiosemicarbazone Schiff base complexes exhibited good scavenging activity against various free radicals (DPPH, OH and NO). The in vitro cytotoxicity of these complexes has been evaluated by MTT assay. The results demonstrate that the complexes have good anticancer activities against selected cancer cell line, human breast cancer cell line (MCF-7) and human skin carcinoma cell line (A431). The DNA cleavage studies showed that the complexes have better cleavage of pBR 322 DNA.     

Synthesis and characterization of new imidophosphanes and phosphine oxides containing 3,3,4,4-tetramethylsuccinimidyl group

A series of new imidophosphanes and phosphine oxides containing 3,3,4,4-tetramethylsuccinimidyl group were synthesized and characterized by ¹H, ¹³C{¹H} and ³¹P NMR spectroscopy, IR and MS. Ph_mPCl_n (m = 3 − n, n = 3, 2, 1) reacted with 3,3,4,4-tetramethylsuccinimide (TH) and potassium 3,3,4,4-tetramethylsuccinimidate 1 to give corresponding Ph_mPT_n. Molecular structures of products were established by single-crystal X-ray diffraction experiments. Attempts to prepare new imidophosphoranes by reactions of 1 with Ph_mPCl_n (m = 5 − n, n = 4, 3, 2) resulted in phosphine oxides. In these reactions the phosphoryl group was formed and we characterized a by-product of this type of reaction.     

C-H activation of benzene by platinum(II) complexes with cyclometalated phosphine ligands

The bulky phosphine ligands di-tert-butyl(1-naphthyl)phosphine (1) or di-tert-butyl(N-indolyl)phosphine (2) react at room temperature with [(μ-SMe₂)PtMe₂]₂. Coordination of the phosphine and C-H bond activation at an sp² carbon of the ligand with the release of methane takes place to form the PC cyclometalated products [(PC)PtMe(SMe₂)] (3 or 4, respectively). The cyclometalated complexes 3 and 4 have both been characterized by X-ray crystallography. Complexes 3 and 4 were each observed to undergo intermolecular activation of arene C-H bonds. Upon thermolysis in benzene, complexes 3 and 4 react to eliminate methane and yield isolable platinum(II)-phenyl complexes.     

Copper(I)-organophosphine complexes of bis(3,5-dimethylpyrazol-1-yl)dithioacetate ligand

Copper(I) complexes have been synthesized from the reaction of CuCl, monodentate tertiary phosphines PR₃ (PR₃ = P(C₆H₅)₃; P(C₆H₅)₂(4-C₆H₄COOH); P(C₆H₅)₂(2-C₆H₄COOH); PTA, 1,3,5-triaza-7-phosphaadamantane; P(CH₂OH)₃, tris(hydroxymethyl)phosphine) and lithium bis(3,5-dimethylpyrazolyl)dithioacetate, Li[LCS₂]. Mono-nuclear complexes of the type [LCS₂]Cu[PR₃] have been obtained and characterized by elemental analyses, FT-IR, ESI-MS and multinuclear (¹H, ¹³C and ³¹P) NMR spectral data; in these complexes the ligand behaves as a κ³-N,N,S scorpionate system. One exception to this stoichiometry was observed in the complex [LCS₂]Cu[P(CH₂OH)₃]₂, where two phosphine co-ligands are coordinated to the copper(I) centre. The solid-state X-ray crystal structure of [LCS₂]Cu[P(C₆H₅)₃] has been determined. The [LCS₂]Cu[P(C₆H₅)₃] complex has a pseudo tetrahedral copper site where the bis(3,5-dimethylpyrazolyl)dithioacetate ligand acts as a κ³-N,N,S donor.     

Metal-metal bonding and charge localisation in [Ru2X9], X=Cl or Br; n=1, 2, 3, 4. A spectroelectrochemical study

A spectroelectrochemical study of [Ru₂X₉]ⁿ⁻, X=Cl, Br; n=1, 2, 3, 4 has been undertaken. Stable solutions of n=4, 2, 1 can be formed by electrolysis at low temperatures. Analysis of the Vis-NIR spectra of the complexes indicate that the Ru^II---R^III dimers (n=4) have delocalised mixed valence and that the Ru^III---R^III (n=3) dimers have a strong Ru---Ru bond. The more oxidised materials do not form a Ru---Ru bond; the spectroscopic data indicates the Ru^III---R^IV dimers have localised valency.     

31P and 195Pt NMR studies on the clusters [Pt4(μ2-CO)5L4]. L = PEt3, PMe2Ph,PMePh2, PEt2But. The molecular structure of a monoclinic modification of [Pt4(μ2-CO)5(PMe2Ph)4].

Several clusters complexes of composition [Pt₄(μ₂-CO)₅L₄] have been synthesized and characterized, using ³¹P and ¹⁹⁵Pt NMR. L = PEt₃, PMe₂Ph, PMePh₂, PEt₂Bu^t. The molecular structure of a new monoclinic modification of the PMe₂Ph derivative has been determined: space group P2₁/n with a = 19.698(4), b = 10.9440(20), and c = 21.360(6) Å, β = 112.432(18)°, Z = 4. Using 4751 reflections measured at 290 ± 1 K on a four-circle diffractometer the structure has been refined to R = 0.0846. The molecule has no imposed symmetry, but the central Pt₄(CO)₅P₄ core has the approximate C₂v architecture established for the previously known orthorhombic modification. The Pt₄ unit is thus a highly distorted, edge-opened (3.3347 Å) tetrahedron, with five edge-bridging carbonyl and four terminal phosphine ligands. In contrast to the crystallographic results ³¹P and ¹⁹⁵Pt NMR spectra reveal equivalent ³¹P and ¹⁹⁵Pt spins, which can be interpreted in terms of a tetrahedral arrangement of platinum atoms. It is suggested that this equivalence arises from time-averaging of all possible isomeric edge-opened tetrahedra.     

Coordination diversity of N-phosphoryl-N′-phenylthiourea (LH) towards Co, Ni and Pd cations: Crystal structure of ML2-N,S and ML2-O,S chelates

Thiourea, PhNHC(S)NHP(O)(OPrⁱ)₂ (LH) chelates of Co^II, Ni^II, and Pd^II ions have been obtained and investigated by single-crystal X-ray diffraction, UV, IR, NMR spectroscopy, and EI mass-spectrometry. The unusual 1,3-N,S-coordination via sulfur and NP(O) nitrogen atoms has been found in the trans-square-planar NiL₂ and PdL₂ complexes, whereas the 1,5-O,S-coordination is realized in the tetrahedral CoL₂ complex. DFT calculations have revealed significant stabilization of the 1,3-N,S-structures due to stronger crystal field and the NH-OP hydrogen bonds.