Thermolysis Of Complexes Research Articles

Synthesis and Photocatalytic Activity of High-Quality Lead(II) Sulfide Nanoparticles from Lead(II) Thiosemicarbazone Complexes as Single Source Precursors

We report the synthesis of lead(II) complexes of 2-(thiophen-2-ylmethylene) hydrazine-1-carbothioamide (1) and 2-(1-(thiophen-2-yl) ethylene) hydrazine-1-carbothioamide (2), which were used as single source precursors in hexadecylamine (HDA) and oleylamine (OLA) at 190, 230, and 270°C to synthesize lead(II) sulfide nanoparticles. Optical studies by UV–vis analysis showed a general blue shift in the absorption band edge of the PbS nanoparticles (NPs) with energy bandgaps determined by Tauc’s plots ranging from 2.15 to 3.11 eV. The development of NPs with a variety of morphologies that changed with temperature and precursor type was demonstrated by morphological characterization using scanning electron microscopy and transmission electron microscopy. Cubic, rod-shaped, and nearly spherical-shaped PbS were formed. Powder X-ray diffraction (p-XRD) structural studies revealed the face-centered cubic structure of PbS nanoparticles. The elements contained in the nanoparticles were identified by energy dispersive X-ray spectroscopy (EDX). These results suggest that the size, shape, and optical properties of the synthesized PbS NPs were affected by reaction temperature, capping group, and precursor type. Under UV irradiation, the photocatalytic activity of HDA-capped PbS nanoparticles on the degradation of methylene blue dye ranged from 28.3% to 60.0%, with lead sulfide nanoparticle obtained by thermolysis of complex (1) at 230°C showing the highest photocatalytic efficiency (60.0%).

An interesting heterometallic complex [{Ni2(κ2-SeC5H4N)2(µ-OCH3)CdCl}2] as single source molecular precursor for NiSe/CdSe heterostructure: Consequence of similar Ni-Se and Cd-Se bond distances

Since Ni and Cd belong to the 3d and 4d series of transition elements respectively, common perception insists that Ni-Se and Cd-Se bond distances in molecular complexes will be quite different. Present work reports the successful synthesis and detailed characterization of cis-configured mononuclear complex [Ni(SeC5H4N)2(dppe)] (1) as well as novel tetranuclear heterometallic Ni-Cd complex [{Ni2(κ2-SeC5H4N)2(µ-OCH3)CdCl}2] (2). Here, the complex [Ni(SeC5H4N)2(dppe)] act as building block for the preparation of complex 2 which has similar Ni-Se and Cd-Se bond distances (within 0.1 Å). The closeness of these bond lengths has facilitated the preparation of NiSe/CdSe heterostructure. The prepared NiSe/CdSe heterostructure has been thoroughly characterized by pXRD, SEM, TEM and EDS, while diffuse reflectance spectroscopy (DRS) was used to evaluate the bandgap of the heterostructure. Detailed structural analysis of molecular assembly further endorses that bond length similarity of Ni-Se and Cd-Se in complex appears as the key factor in getting the heterostructure upon thermolysis of complex. DFT calculations revealed that underlying spin moments of heterometallic system commands the complex to have Ni-Se and Cd-Se bond distances within 0.1 Å range. The magnetic interactions in complex were reaffirmed by weak ferromagnetic ordering observed in superconducting quantum interference device (SQUID) analysis of molecular assembly at lower temperature. It is believed that controlled preparation of NiSe/CdSe heterostructure from novel single source heterometallic precursor reported in the present work will assist the synthesis of functional chalcogenide materials with technological importance.

СИНТЕЗ ОКТЕНІДИНУ ГЕКСАФТОРОСИЛІКАТУ – НОВОГО ПОТЕНЦІЙНОГО КАРІЄСПРОФІЛАКТИЧНОГО І АНТИБАКТЕРІАЛЬНОГО АГЕНТА

Мета роботи. Здійснити синтез октенідину гексафторосилікату як потенційного карієспрофілактичного і антибактеріального препарату.Матеріали і методи. Вихідні реагенти, октенідину дигідрохлорид і кремнефтороводнева кислота є комерційно доступними реактивами. ІЧ-спектри поглинання реєстрували на спектрофотометрі Spectrum BX II FT-IR System (Perkіn-Elmer), мас-спектри FAB – спектрометрі VG 7070 (VG Analytіcal), спектри ЯМР 1H, 19F – на спектрометрі Varіan Gemini-400. Термогравіметричний аналіз проводили на дериватографі Q-1500 D системи F. Paulik – J. Paulik – L. Erdey.Результати й обговорення. Одержано октенідину гексафторосилікату моногідрат на основі реакції іонного обміну між метанольним розчином октенідину дигідрохлориду і кремнефтороводневою кислотою. Склад і іонна будова синтезованої сполуки підтверджено методами ІЧ-, ЯМР 1H, 19F-спектроскопії, мас-спектрометрії. Термоліз комплексу супроводжується процесами дегідратації і деструкції з подальшим окисленням фрагментів катіону.Висновки. Синтезовано октенідину гексафторосилікату моногідрат, нове похідне октенідину, що становить інтерес як потенційний карієспрофілактичний і антибактеріальний засіб.

COORDINATION COMPOUNDS OF TIN(IV) WITH HYDAZEPAM AND PRODUCTS OF ITS CONDENSATION WITH ARYLALDEHYDES

Reaction of tin tetrachloride in a 2-propanol solution and 2-(7-bromo-2-oxo-5-phenyl-3H- 1,4-benzodiazepin-1-yl)acetohydrazide (“gidazepam”, hydazepam – HHy) made it possible to obtain for the first time the corresponding tin coordination compound [Sn(HHy)Cl4] (I). A synthetic technique of the template synthesis has been developed and a novel coordination compounds [Sn(HHySl)Cl3] (II), [Sn(HHySlNO2)Cl3] (III), [Sn(HHy2Nf)Cl3] (IV), [Sn(HHy2NfBr)Cl3] (V) in the systems HHy–(HSl, HSlNO2, H2Nf, H2NfBr)–SnCl4–2-propanol, where HSl is 2-hydroxybenz-, HSlNO2 – 2-hydroxy-5-nitrobenz-, H2Nf – 1-hydroxy- 2-naphth-, H2NfBr – 4-bromo-1-hydroxy-2-naphth-aldehydes, have been synthesized. They are crystalline substances readily soluble in DMF and acetonitrile and moderately soluble in ethanol. The composition and structure of the complexes were confirmed by a number of physicochemical methods: elemental analysis, electrical conductivity, mass spectrometry, IR spectroscopy and thermogravimetry. The measurement of the electrical conductivity of solutions of the I−V in DMF has shown that they all are non-electrolytes. It was found by the thermogravimetric method that the thermolysis of complexes I−V proceeds uniformly and is stepwise in nature. The presence of peaks of molecular ions of the corresponding hydrazones in the mass spectra of complexes II−V obtained by template synthesis confirmed the formation of these hydrazones and the participation in coordination to the Sn4+ ion in the reaction course. Tin(IV) coordination polyhedron in all complexes is the octahedron formed by: four chlorine atoms, the nitrogen atom of the hydrazide amino group and the oxygen atom of the ligand carbonyl group in I; three chlorine atoms, azomethine nitrogen atom and two oxygen atoms of the carbonyl and deprotonated hydroxy group of the ligand in II−V.

Phase controlled synthesis of copper sulfide nanoparticles by colloidal and non-colloidal methods

Bis(O-alkylxanthato)copper(II) (alkyl = Et (1), Hex (2) and Oct (3)) complexes were synthesized and used as single source precursors for the synthesis of copper sulfide nanoparticles by thermolyses in oleylamine, solid state deposition and doctor’s blade method at different temperatures and reaction times. The p-XRD pattern of the copper sulfide nanoparticles obtained from complex (1) by colloidal thermolysis in oleylamine show pure Digenite phase (Cu9S5) under all reaction conditions. TEM images show significant changes in size and shape of crystallites by variation of the growth temperature or time. Thermolysis of complex (2) in oleylamine gave pure phase Digenite (Cu9S5) at higher temperature (250 °C) with disks and rectangular cuboidal morphologies whereas at lower temperature (200 °C) traces of Covellite (CuS) were also observed. The p-XRD analysis of the nanoparticles produced from the thermolysis of complex (3) in oleylamine show Digenite (Cu9S5) as the predominant phase with some impurity of Djurleite (Cu31S16) phase. The melt method produced Digenite and Covellite phases from complex (1) and pure Digenite phase from complex (2). Complex (3) gave the Digenite and Chalcocite phases. Nanoparticles from all three complexes by the melt method show spherical and cuboid morphology. p-XRD of thin films by the doctor blade method show Digenite as the major phase and Djurleite as the minor phase. These results showed that the phase of copper sulfide were directly dependent on the type of precursor (alkyl chain length), growth temperature and the method used.

Synthesis, spectral, thermal, crystal structure, Hirschfeld analysis of [bis(triamine)Cadimium(II)][Cadimum(IV)tetra-bromide] complexes and their thermolysis to CdO nanoparticles.

BackgroundThe coordination chemistry of cadmium(II) with diamine ligands is of particular interest. The most common structure around cadmium(II) center in their complexes is tetrahedral, that is due the octet rule obeyed. Nevertheless, five and six-coordinated complexes are also well known. Now a day, many cadmium(II) complexes with chelate ligands were synthesized for their structural or applications properties. Antibacterial activities and DNA binding affinity of this class of cadmium complexes have attracted considerable interest.ResultsCadmium(II) complexes in dicationic form with general formula [Cd(dien)2]CdBr4 complex 1 (dien = diethylenetriamine) and [Cd(dipn)2]CdBr4 complex 2 (dipn = diproylenetriamine) were prepared and elucidated there chemical structures by elemental analysis, UV–Vis, IR, TG and NMR, additionally complex 1 structure was solved by X-ray diffraction study. The Cd(II) cation is located in a slightly distorted octahedral geometry while Cd(IV) anion is in tetrahedral geometry. High stability of the synthesized complexes confirmed by TG. Thermolysis of complex 1 revealed the formation of pure cubic nanoparticles CdO which was deduced by spectral analysis. The average size of CdO nanoparticles was found to be ~60 nm.ConclusionsTwo new Cd(II) complexes of general formula [Cd(N3)2]CdBr4 were made available. The structure of [Cd(dien)2]CdBr4 was confirmed by X-ray diffraction. Thermal, electro and spectral analysis were also investigated in this study. The direct thermolysis of such complexes formed a cubic CdO regular spherical nanoparticle with the ~60 nm average particle size.Graphical abstractORTEP for the complex 1

Synthesis, structure, and physical properties of new rare earth ferrocenoylacetonates.

New ferrocenoylacetonate complexes of several rare earth elements, [Ln(fca)3(bpy)]·MeC6H5 (Ln = Pr (), Eu (), Gd (), Tb (), Dy (), Ho (), Y (); bpy - 2,2'-bipyridine; Hfca - FcCOCH2COMe) as well as scandium ferrocenoylacetonate [Sc(fca)3]·0.5MeC6H5 (), were synthesized and characterized by single crystal X-ray diffraction analysis. In the crystal lattice of the isostructural complexes , two [Ln(fca)3(bpy)] molecules form a pair due to stacking interactions between the bpy ligands. The Ln(3+) ions are coordinated in a square antiprism geometry with a coordination number of 8. The Sc(3+) ions in complex are coordinated in an octahedral geometry. Thermolysis of complexes was studied under air and argon atmospheres; in the first case, it affords perovskites LnFeO3 as one of the products. Complexes display single-molecule magnet properties, and the effective relaxation barrier for the Dy complex , was found to be Δeff/kB = 241 K, which is one of the highest values obtained for a mononuclear β-diketonate lanthanide complex.

Thermolysis of binuclear heterometallic pivalate with Pd(II)-Ce(III) metal core in dibenzyl ether

A reaction between palladium(II) acetate and aqueous cerium(III) acetate in acetic acid with subsequent boiling in benzene with excess pivalic acid is found to yield the complex Pd(μ-OOCBut)4Ce(OOCBut)(HOOCBut)3 (1). The liquid-phase thermolysis of complex 1 in dibenzyl ether (190°C) leads to the formation of the tetranuclear complex [Pd(μ-OOCBut)4Ce(HOOCBut)]2(μ-OOCBut)(μ-OH2) (2). The structure of the synthesized complexes is established by X-ray diffraction.

Synthesis, characterization and thermolysis of lanthanide metal nitrate complexes with 1, 10-phenanthroline, Part-95

The nitrate complexes of cerium, praseodymium and neodymium with 1,10-phenanthroline (phen) of general formula [Ln(phen)2(NO3)2(H2O)2]·NO3 (where, Ln=Ce, Pr and Nd) were prepared and characterized by X-ray crystallography. Thermolysis of these complexes was investigated by simultaneous thermogravimetry (TG) and differential thermal analysis (DTA). Isothermal TG was taken to evaluate the kinetic parameters using model fitting as well as model free isoconversional methods. The thermolytic pathways were also suggested, which involves decomposition followed by ignition. All the three complexes had coordination number ten and showed multistep decompositions. In order to evaluate the response of rapid heating, ignition delay (Di) measurements were undertaken. The activation energies for ignition were found to decrease in the order: Nd>Pr>Ce.

Synthesis, structures, and thermolysis of new heterometallic cobalt, nickel, and copper complexes with the [Ru(NO)(NO2)4(OH)]2− anion as a ligand

Heterometallic complexes with pyridine-N-oxide (PyO), Ru(NO)(NO2)4(OH)Ni(PyO)2(H2O)] · CH3COCH3 (I), [{Ru(NO)(NO2)2(μ-NO2)2(μ-OH)Co}2(μ-PyO)] · H2O · CH3COCH (II), and [Ru(NO)(NO2)4(OH)Cu(PyO)2 (III), are isolated in the reactions of Na2[Ru(NO)(NO2)4(OH)] with nitrates of the corresponding metals in the presence of the organic ligand. The compounds synthesized are characterized by IR spectra, thermal analysis, and X-ray diffraction analysis. Depending on the M2+ cation, the ruthenium cation is coordinated through the bidentate (III, Cu2+) or tridentate (I, Ni2+ and II, CO2+) mode involving the bridging OH group and one or two NO2 groups. The thermal decomposition of complex II results in the formation of a Co0.5Ru0.5 solid solution, which is thermodynamically stable under the decomposition conditions. The thermolysis of complexes I and III in a hydrogen atmosphere leads to the formation of metastable solid solutions.

Hexaaquacobalt(II) and hexaaquacadmium(II) 4-nitro-2,3,5,6-tetraoxopyridinates [M(H2O)6](C5HN2O6)2 · 2H2O (M = Co and Cd): Synthesis, structures, and properties

The complexes [Cd(H2O)6](C5HN2O6)2 · 2H2O (I) and [Co(H2O)6](C5HN2O6)2 · 2H2O (II) were obtained in the crystalline state by reactions of cobalt chloride and cadmium chloride with ammonium 4-nitro-2,3,5,6-tetraoxopyridinate, (NH4)2 · (C5HO6N2)2. Their cocrystallization gave the heterometallic complex [Cd0.32Co0.68(H2O)6](C5HN2O6)2 · 2H2O (III). The crystal and molecular structures of complexes I-III were determined by X-ray diffraction. It was demonstrated that the complexation reactions occur by replacement of two ammonium cations 4-nitro-2,3,5,6-tetraoxopyridinate by the complex cations [M(H2O)6]2+. The tetraoxopyridinate anions and the complex cations are hydrogen-bonded through the coordinated and crystallization water molecules as well as through the O atoms of the organic anion. The thermolysis of complexes I and II was examined by TGA.

Synthesis of finely disperse nickel particles by thermolysis of complex (N2H5)[Ni(NH2NHCOO)3] · H2O in organic liquids and refinement of crystal structure of this complex

The crystal structure of the complex (N2H5)[Ni(NH2NHCOO)3] · H2O (I) was refined using X-ray diffraction data (obtained on an Apex X8 diffractometer, MoKα radiation, 1830 Fhkl, R = 0.0182). The structure is built of complex anions [Ni(NH2NHCOO)3]−, cations N2H5+, and water molecules and is characterized by strong hydrogen bonds N-H…O, O-H…O, and N-H…N. The N3O3 coordination polyhedron around a Ni atom is a slightly distorted octahedron. The thermal decomposition of complex I was studied in high-boiling organic liquids. The feasibility of preparing non-pyrophoric nickel powders having particle sizes of up to 20 nm is shown.

Stabilizing High-Valent Metal Ions with a Ketimide Ligand Set: Synthesis of Mn(N═CtBu2)4

Reaction of MnCl(2) with 4 equiv of Li(N=C(t)Bu(2)) generates [Li(THF)](2)[Mn(N=C(t)Bu(2))(4)] (1) in 80% yield. Oxidation of 1 with 0.5 equiv of I(2) produces [Li][Mn(N=C(t)Bu(2))(4)] (2) in 88% yield. Both complexes 1 and 2 exhibit tetrahedral structures about the Mn center in the solid-state, as determined by X-ray crystallography. Reaction of 2 with 12-crown-4 generates [Li(12-crown-4)(2)][Mn(N=C(t)Bu(2))(4)] (3) in 94% yield. Interestingly, in the solid-state, complex 3 exhibits a squashed tetrahedral structure about Mn. Addition of 1 equiv of I(2) to 1 generates the Mn(IV) ketimide, Mn(N=C(t)Bu(2))(4) (4), in 75% yield. Complex 4 was fully characterized, including analysis by X-ray crystallography and cyclic voltammetry. Like 3, complex 4 also exhibits a squashed tetrahedral structure in the solid-state. Interestingly, thermolysis of complex 4 at 50 °C for 6 h results in the formation of Mn(3)(N=C(t)Bu(2))(6) (6), which can be isolated in 49% yield. Also observed in the reaction mixture is pivalonitrile, isobutylene, and isobutene, the products of ketimide ligand oxidation. We have also synthesized the homoleptic Cr(IV) ketimide complex, Cr(N=C(t)Bu(2))(4) (5), and have analyzed its electrochemical properties with cyclic voltammetry.

Titanoxycarbene complexes of Ti(iv) with O- and N-donor ligands

Heterobimetallic complexes of the general formula [{(OC)5MC(Me)OTi(OiPr)2}(µ-OiPr)]2 with M = Cr (1), W (2) were synthesized by reacting (OC)5MC(Me)OLi (M = Cr, W) with ClTi(OiPr)3. X-Ray crystallography revealed dimeric molecular structures based on four-membered Ti2O2-rings for both compounds. Most intriguingly crystals of 1 virtually “shattered” upon cooling below −60 °C. Treatment of 1 and 2 with an excess of pyridine did not effect symmetric cleavage of the dimers, but afforded the unique rearrangement products [(OC)5MC(Me)O]2Ti(OiPr)2(C5H5N)2 with M = Cr (3) and W (4). The isomorphous structures, determined by means of X-ray diffraction, are only the second examples of an unrestrained titanium center coordinated by four OR and two N-donor ligands. Complexes 3 and 4 were also accessible from Cl2Ti(OiPr)2(C5H5N)2 (5) and (OC)5MC(Me)OLi. Owing to the inherent dynamic behaviour of all complexes, low-temperature NMR studies were undertaken. The formation of nanoparticles upon thermolysis of complex 2 lends support to the notion that the presented (or related) compounds could be useful as single source precursors for nano-sized mixed metal oxides or oxo nitrides.

Synthesis, molecular structures, and properties of heterometallic cobalt tetramethylcyclobutadiene complexes (C4Me4)Co(CO)2TePh, (C4Me4)Co(CO)2TePh[W(CO)5], and Me4C4Co(μ3-S)2Cr2Cp2(μ-SC4H9)

The reaction of Cb*Co(CO)2I (1) (Cb* is tetramethylcyclobutadiene) with sodium phenyltelluride afforded the mononuclesar complex Cb*Co(CO)2TePh (2). The reaction of the latter with W(CO)5(THF) produced the Cb*Co(CO)2TePh[W(CO)5] compound (4). The reaction of 1 with the Cp2Cr2(SCMe3)2S complex gave the heterometallic cluster Cb*Co(μ3-S)2Cr2Cp2 (μ-SCMe3) (5). Complexes 2, 4, and 5 are diamagnetic. Their structures were determined by X-ray diffraction. Complex 2 contains the Co-Te bond (2.585(1) A); complex 4, the Co-Te (2.558(8) A) and W-Te (2.8467(6) A) bonds. Complex 5 has the stable triangular sulfide-and tert-butylmercaptide-bridged core Cr2Co (Cr-Cr and Cr-Co bond lengths are 2.626(2) and 2.673(2) A, respectively) with Cp ligands at the chromium atoms and a Cb* ligand at the cobalt atom. Complex 5 was characterized by cyclic voltammetry. The thermolysis of complex 4 was studied.

Effect of ligands on the thermolysis of the double complexes [Co(NH3)6]2C2O4[Cu(C2O4)2]2 and [Co(NH3)6]Cl[Cu(C7H4O3)2

The thermolysis of the complexes [Co(NH3)6]2C2O4[Cu(C2O4)2]2 (I) and [Co(NH3)6]Cl[Cu(C7H4O3)2] (II) in air and hydrogen at 200, 350, and 500°C and the composition and properties of the thermolysis products are considered. The oxidative thermolysis of the complexes yields mixtures of cobalt and copper oxides, including mixed ones. The reductive thermolysis of the complexes yields a Co + Cu bimetallic powder in the case of compound I and a Co + Cu + C powder in the case of compound II. The thermal behavior of the complexes is governed by the nature of the ligand coordinated to the copper atom. The observed data are explicable in terms of the properties of this ligand. The chemistry of the oxidative and reductive thermolysis is discussed.

Anion effect on the thermolysis of double complexes [Co(NH3)6][Fe(CN)6] and [Co(NH3)6]4[Fe(CN)6

The thermolysis of complexes [Co(NH3)6][Fe(CN)6] and [Co(NH3 6]4[Fe(CN)6]3 under an air or hydrogen atmosphere at 200, 350, and 500°C is studied. The composition and properties of thermolysis products are determined. The oxidative thermolysis yields mixtures of oxides of the central metals; the reductive thermolysis yields intermetallic compounds CoFe. The density of the complexes and the specific surface area of the intermetallic compounds are measured. Average particle sizes are calculated. The morphology and dispersion of the powders are dictated by the shape and density of the crystals of the precursor double salts and the thermolysis temperature. The thermolysis chemism in the oxidative and reductive atmospheres is discussed in the context of the nature of the complex anion.

SYNTHESES, STRUCTURES AND REACTIONS OF NEW AND NOVEL FOUR-, FIVEAND SIX-MEMBERED UNSATURATED N,P-HETEROCYCLE COMPLEXES

Metal-assisted heterocyclic ligand syntheses are reported using 2-H-azaphosphirene complex 1 or 7-phosphanorbornadiene complex 7 as starting material. Thermal decomposition of complex 1 led to 1,2dihydro-1,2,3-azadiphosphete complex 2, which was transformed into 2,6-dihydro-1,3,2,6-diazadiphosphinines 5a, b via ring expansion with carbonitriles 3a, b. Insertion of tert-butyl isonitrile into the P─ P bond of 2 at ambient temperature furnished the first Δ 1 -1,3,5-azadi-phospholene complex 6─P bond of 2 using 7 failed. The 1,2,3,4-azatriphospholene complexes 9a, b were obtained by thermolysis of complex 2 in the presence of functionalized carbonitriles 8a, b.

Catalytic Carbon−Carbon Bond Activation and Functionalization by Nickel Complexes

The nickel alkyne complexes (dippe)Ni(PhC⋮CPh), 1, (dippe)Ni(MeC⋮CMe), 2, (dippe)Ni(MeO2CC⋮CCO2Me), 3, (dippe)Ni(CH3OCH2C⋮CCH2OCH3), 4, and (dippe)Ni(CF3C⋮CCF3), 5, were synthesized (dippe = bis(diisopropylphosphino)ethane) and characterized by 1H, 31P, and 13C{1H} NMR spectroscopy. Complexes 1, 2, and 3 were characterized by X-ray crystallography. The thermolysis of complex 1 or 2 (120 °C) in the presence of excess biphenylene and excess alkyne results in very slow catalytic formation of the corresponding 9,10-disubstituted phenanthrene. However, addition of ∼6 mol % O2 (based on the metal complex) to the reaction mixture results in an acceleration in catalysis at lower temperatures (∼70−80 °C). The thermolysis of complexes 3 or 4 with excess biphenylene and excess alkyne leads to the alkyne cyclotrimerization product as the major organic species formed in the reaction. Fluorenone was catalytically produced by heating (dippe)Ni(CO)2, biphenylene, and CO. Catalytic insertion of 2,6-xylylisocyanide into the strained C−C bond of biphenylene was also achieved by heating (dippe)Ni(2,6-xylylisocyanide)2, excess biphenylene, and 2,6-xylylisocyanide. Mechanistic schemes are proposed for these reactions.

Amide Complexes of Zirconium, Rhodium, and Iridium: Synthesis and Reactivity. X-ray Crystal Structures of (η5-C5H5)2Zr(NHC6H4-o-SMe)2 and [Rh(μ-SC6H4-o-NHMe)(COD)]2

The reaction of Cp2ZrCl2 (Cp = η5-C5H5) with 2 equiv of the lithium amide derivative LiNHC6H4-o-SMe affords the new zirconium complex Cp2Zr(NHC6H4-o-SMe)2 (2). The structure of 2 has been determined by X-ray diffraction. When the reaction is carried out in an 1:1 ratio, the complex Cp2ZrCl(NHC6H4-o-SMe) (3) is generated as the major product. Reaction of “Cp*2Zr” (Cp* = η5-C5Me5) with 2-(methylmercapto)aniline yields a hydride−amide complex Cp*2ZrH(NHC6H4) (4). Reaction of complex 2 with [RhCl(COD)]2 generates complex 3 and the new rhodium amide complex Rh(NHC6H4-o-SMe)(COD), which has been also directly synthesized by reacting [RhCl(COD)]2 with LiNHC6H4-o-SMe. Thermolysis of complex 6, at 100 °C, produces to a new rhodium thiolate complex [Rh(μ-SC6H4-o-NHMe)(COD)]2 (5). Its structure has been determined by X-ray diffraction methods. Reaction of [IrCl(COD)]2 with LiNHC6H4-o-SMe gives the iridium(III) complex Ir(Me)(SC6H4NH)(COD) (7) by oxidative addition of the S−Me bond.