Sandip Dey

Synthesis and characterization of benzylselenolate complexes of palladium(II) and platinum(II)

Reactions of sodium benzylselenolate with several palladium(II) and platinum(II) complexes were carried out and a variety of products isolated and characterized. Reactions of Na2PdCl4 or K2PtCl4 with NaSeBz gave [M(SeBz)2]n (M Pd or Pt; BzCH2Ph) which when treated with tertiary phosphines yielded [M(SeBz)2(L-L)]. The latter can also be prepared by the reaction of MCl2(L-L) (L-Ldppm, dppe or 2PPh3) with NaSeBz. Treatment of [M2X2(m-Cl)2(PR3)2] with NaSeBz in 1:2 molar ratio afforded complexes of the type [M2X2(m-SeBz)2(PR3)2 ]( M Pd or Pt; X Cl or Me; PR3 PEt3, PPr n, PBu n, PMe2Ph, PMePh2 or PPh3) which existed predominantly as a cis isomer. Reaction of [M2Cl2(m-Cl)2(PR3)2] with [M2Cl2(m-SeBz)2(PR3)2] gave heterobridged complexes [M2Cl2(m-Cl)(m-SeBz)(PR3)2], the bridging chloride in the latter can be substituted with SBu t or pz. All the complexes were characterized by elemental analysis and NMR ( 1 H, 31 P, 77 Se, 195 Pt) spectral data. Stereochemistry of these complexes has been discussed on the basis of NMR data. The crystal structure of [Pt2Cl2(m-SeBz)2(PPr n )2] has established a cis configuration with a bent four-membered Pt2Se2 ring. The complex [Pd(SeBz)2]n on thermolysis at 630°C yields Pd17Se15.

Synthesis and characterization of 3-dimethylaminopropyl selenolate complexes of palladium(II) and platinum(II)

Abstract Bis(3-dimethylaminopropyl)diselenide was prepared by the reaction of Na2Se2 with Me2NCH2CH2CH2Cl. 3-Dimethylaminopropylselenolate complexes of palladium and platinum of the formulae [M(SeCH2CH2CH2NMe2)Cl]2, [M(SeCH2CH2CH2NMe2)2] (M=Pd or Pt), [Pd(OAc)(SeCH2CH2CH2NMe2)], [PtCl(SeCH2CH2CH2NMe2)(PR3)]2 (PR3=PMePh2 or PPr3), [Pt(SeCH2CH2CH2NMe2)2(PP)] (PP=dppm, dppe or 2PPh3) have been synthesized by using either the diselenide or its reduction product from the reaction with NaBH4. All complexes have been characterized by elemental analysis, IR and NMR (1H, 13C, 31P, 77Se, 195Pt) spectroscopy. The stereochemistry of these complexes has been deduced from the NMR spectroscopic data. The structure of [Pd(SeCH2CH2CH2NMe2)Cl]2 was established by single crystal X-ray diffraction analysis. Each palladium atom in the dimer is surrounded by two μ-Se atoms, a nitrogen atom and a chloride ligand.

Platinum(II) Complexes of 2-(Dimethylamino)ethylselenolate − Donor−Acceptor Inter-Ligand Interactions as Evident from Experimental and TD-DFT Computational Analysis

Several platinum(II) complexes of 2-(dimethylamino)ethaneselenolate with the formulae, [PtCl(SeCH2CH2NMe2)(PR3)] (1), [PtPh(SeCH2CH2NMe2)(PnBu3)] (2), [Pt2Ph2(Cl)(SeCH2CH2NMe2)(PnBu3)2] (3), [Pt2Cl3(SeCH2CH2NMe2)(PR3)2] (4), [Pt(SeCH2CH2NMe2)2(P−P)] (5), [Pt2(SeCH2CH2NMe2)2(P−P)2]++ (6), and [Pt(SeCH2CH2NMe2)(PPh3)]n[PF6]n (7) have been synthesized and characterized by elemental analysis, UV/Vis and NMR (1H, 31P, 77Se, 195Pt) spectroscopy. The stereochemistry of these complexes (1−7) has been deduced from NMR spectroscopic data. A weak absorption in the UV/Vis spectrum of 1 has been assigned to a ligand (Se)-to-ligand (PR3) charge transfer (LLCT), supported by TD-DFT calculations. The structures of [PtCl(SeCH2CH2NMe2)(PPh3)] and [Pt2Ph2(Cl)(SeCH2CH2NMe2)(PnBu3)2] have been established by single crystal X-ray diffraction analysis. Each platinum atom in the latter is coordinated to four different ligands and Me2NCH2CH2Se behaves as μ2-bridging and is also simultaneously chelated to one of the platinum atoms.

Hemilabile silver(I) complexes containing pyridyl chalcogenolate (S, Se) ligands and their utility as molecular precursors for silver chalcogenides

A series of silver triphenylphosphine complexes containing pyridyl chacogenolate (S, Se) ligands has been synthesized by employing [AgCl(PPh3)3] and [Ag2(μ-Cl)2(PPh3)4]. The complexes [Ag(S-4-pyH0.5)2(PPh3)2] (1) and [Ag2(μ-S-4-py)2(PPh3)4] (2) were obtained by the reactions of [Ag2(μ-Cl)2(PPh3)4] with 4-pySH in the presence of Et3N and NaOH, respectively. The former has a hydrogen-bonded chain-like structure, while the latter possesses a discrete binuclear structure. 2 on heating in methanol afforded a two-dimensional coordination polymer, [Ag2(μ-S-4-py)2(PPh3)2]n (3). The reaction of [Ag2(μ-Cl)2(PPh3)4] with NaSe-4-py gave [Ag3(μ-Se-4-py)3(PPh3)4] (4) as the primary product together with a minor mononuclear complex, [Ag(Se-4-py)(PPh3)3] (5). The latter could be obtained in excellent yield under the same conditions utilising [AgCl(PPh3)3] as the starting material. Complex 5 on recrystallization afforded 4. The reaction of [AgCl(PPh3)3] with NaS-2-py yielded [Ag(S-2-py)(PPh3)3] (6). Complexes 2–6 on refluxing in chloroform gave insoluble polymeric complexes of composition [Ag(Epy)]n (7) (Epy = 4-pyS (7a), 4-pySe (7b), 2-pyS (7c)) which on thermolysis yielded Ag2E (E = S, Se). The molecular structures of these complexes (1–6) have been established unambiguously by single-crystal X-ray diffraction analyses. Non-bonding interactions in the molecular structures have been discussed.

Synthesis and structure of bis(2-N, N-dimethylamioethyl-selenolato)zinc and its transformation to ZnSe

Abstract The air-stable compound [Zn(SeCH2CH2NMe2)2] (1) as prepared from Zn(OAc)2·2H2O and 2 equiv. of NaSeCH2CH2NMe2 contains monomeric molecules with a characteristically distorted tetrahedral zinc atom coordinated to two selenium and two nitrogen atoms. On thermolysis 1 yields ZnSe which was characterized by XRD.

Organochalcogenolates of Palladium(II) and Platinum(II): Versatile Molecular Precursors for Metal Chalcogenides

This presentation intends to discuss the design and synthesis of low temperature single source molecular precursors for the synthesis of palladium chalcogenides, both in bulk and nano-size regime. Thus a variety of organochalcogenolates of palladium and platinum differing in nuclearity (mono-, bi-, tri- and hexa- nuclear) have been isolated and characterized by uv-vis, NMR ( 1 H, 13 C, 31 P, 77 Se, 125 Te, 195 Pt) spectroscopy and X-ray crystallography. Thermal behavior of several complexes, such as [Pd(SeCOAr) 2 (PR 3 ) 2 ], [Pd(OAc)(ECH 2 CH 2 CH 2 NMe 2 )] 2 , etc. has been studied by TG analyses. Solvothermal decomposition yields palladium chalcogenides nano-particles (e.g., Pd 7 Te 3 , Pd 17 Se 15 ) which were characterized by XRD, EDAX and SEM method.

Synthesis of Undoped and Manganese-Doped HgTe Nanoparticles Using [Hg(TeCH 2 CH 2 NMe 2 ) 2 ] as a Single Source Precursor

The Reaction of [HgCl2(tmeda)] with NaTeCH2CH2NMe2 gave a mercury tellurolate, [Hg(TeCH2CH2. NMe2)2] (1) as a yellow crystalline solid, which was characterized by elemental analysis, UV-vis, mass and NMR (1H, 13C, 125Te, 199Hg) spectroscopy. Thermolysis of 1 in hexadecylamine (HDA) at 90 degrees C in the absence and presence of Mn(OAc)2.4H2O gave undoped and Mn-doped HgTe nanoparticles which were characterized by XRD, EDAX, TEM, EPR and magnetic measurements. These particles could be synthesized with mean particle size of 6-7 nm (from TEM). Manganese substitution at Hg site in HgTe lead to a linear decrease in lattice parameter with increasing concentration of Mn. Magnetization measurements showed ferromagnetic ordering at room temperature with very small coercive field (Hc, 50 Oe) for Hg0.973 Mn0.027 Te sample. This sample also exhibited distinct ferromagnetic resonance (FMR) in the EPR spectrum.

CCDC 1823694: Experimental Crystal Structure Determination

Related Article: Manoj K. Pal, Sandip Dey, Amey P. Wadawale, Nisha Kushwah, Mukesh Kumar, Vimal K. Jain|2018|Chem. Sel.|3|8575|doi:10.1002/slct.201801617

CCDC 1515535: Experimental Crystal Structure Determination

Related Article: Sandip Dey, Tianyi Zhang, Nattamai Bhuvanesh, John A. Gladysz|2017|J.Organomet.Chem.|849-850|237|doi:10.1016/j.jorganchem.2017.05.006

Coordination Polymers of Palladium Bridged by Carboxylate and Dimethylaminoalkylselenolate Ligands.

Coordination polymers of palladium stabilized by dimethylaminoalkylselenolate and carboxylate ligands are reported. The reaction of [PdCl(SeCH2 CH2 NMe2 )]3 with AgOTf followed by treatment with sodium acetate afforded [Pd(0) Pd(II) 4 (SeCH2 CH2 NMe2 )3 (OAc)3 ](OTf)2 (1) in which one of the Pd atoms is in the zero oxidation state. In the absence of NaOAc, a tetranuclear complex, [Pd(II) 4 (SeCH2 CH2 NMe2 )4 (OTf)](OTf)3 (2), is isolated from the same reaction. Subsequent treatment with NaO2 CR afforded [Pd4 (SeCH2 CH2 NMe2 )4 (O2 CR)4 ] (R=tBu (3) and Ph (4)). The reaction of [PdCl(SeCH2 CH2 CH2 NMe2 )]2 with AgOTf and NaOAc yielded an ionic binuclear complex, [Pd(II) 2 (SeCH2 CH2 CH2 NMe2 )2 (OAc)](OTf) (5). These complexes have been characterized by NMR spectroscopy, crystal structures, and in some cases by X-ray photoelectron spectroscopy, cyclic voltammetry and mass spectrometry. Complexes 1 and 5 are associated through secondary interactions and coordinate bonds, respectively, to generate polymeric structures in the solid state.