Computational Investigation of Solvent Effect on Stability,Electronic and Thermochemical Properties of Iron-Substituted Borirene and Boryl Isomers

This study investigates solvent effect on several electronic structure features, i.e. structural stability, orbital energies, HOMO-LUMO gaps and hardness of an iron aminoborirene complex [(η⁵-C₅H₅)(OC)₂Fe{μ- BN(SiH₃)₂C=C}Ph] (closed-isomer) and its isomer the boryl complex [(η⁵-C₅H₅)(OC)₂FeBN(SiH₃)₂C≡CPh] (open-isomer) through polarizable continuum model. Results revealed that the closed isomer is less stable than the open isomer, in solvent. Further, influence of the solvent on the frontier orbitals energies, HOMOLUMO gap, electrophilicity and chemical potential energies of the isomers was studied. Thermochemical analysis was conducted to study closed-open equilibrium and thermochemical parameters (ΔG and ΔH) were computed.     

Synthesis and structure of silicon-containing <Emphasis Type="Italic">N</Emphasis>-methyland <Emphasis Type="Italic">N</Emphasis>-benzoylamides of diisopropylphosphoric acid

Diisopropyl N-benzoyl-N-(trimethylsilyl)phosphoramidate reacts with ClCH₂SiMe₂Cl under mild conditions to form diisopropyl N-benzoyl-N-[(chlorodimethylsilyl)methyl]phosphoramidate (III). Diisopropyl N-methyl-N-(trimethylsilyl)phosphoramidate with ClCH₂SiMe₂Cl affords an N-transsilylation product which does not rearrange into diisopropyl N-[(chlorodimethylsilyl)methyl]-N-methylphosphoramidate (XV) even under severe conditions (4 h, 130°C). Compound XV was prepared by the reaction of diisopropyl phosphorochloridate with N-[(methoxydimethylsilyl)methyl]-N-methylamine followed by treatment of diisopropyl N-[(methoxydimethylsilyl)methyl]-N-methylphosphoramidate with boron trichloride. Analysis of experimental and calculated ²⁹Si chemical shifts points to a five-coordinate silicon atom in compound III and a fourcoordinate silicon atom in compound XV. According to B3LYP calculations with due regard to solvent effects, compound III is an isomer with a C=O→Si bond. By variation of substituents at silicon, phosphorus, and carbonyl carbon atoms, chelate structures with either C=O→Si or P=O→Si dative bonds can be obtained.     

Analysis of the Interaction Between the C<Subscript>20</Subscript> Cage and <Emphasis Type="Italic">cis</Emphasis>-Ptcl<Subscript>2</Subscript>(NH<Subscript>3</Subscript>)<Subscript>2</Subscript>: A DFT Investigation of the Solvent Effect,Structures, Properties,and Topologies

This study investigates the interaction between C²⁰ and the cis-PtCl₂(NH₃)₂ complex using MPW1PW91 quantum chemical calculations in gas and solution phases. Two interaction modes between C²⁰ and the cis-PtCl₂(NH₃)₂ complex are considered: I-isomer (η₂-C²⁰) and II-isomer (η₁-C²⁰). It also determines the effects of the solvent polarity on the dipole moment, electronic spatial extent (ESE), structural parameters, and frontier orbital energies of two possible isomers of the C²⁰…cis-PtCl₂(NH₃)₂ complex. The bonding interaction between C²⁰ and the cis-PtCl₂(NH₃)₂ complex was examined through energy decomposition analysis (EDA). The metal–ligand bonds are evaluated using the percentage composition of the specific groups of frontier orbitals. The quantum theory of atoms in molecules (QTAIM) analysis is applied to assess the Pt–C bonds within the complex. Finally, the Pt–C spin-spin coupling constants are calculated using the gauge independent atomic orbital (GIAO) method.     

Platinum trans‐Bis(borirene) Complexes Displaying Coplanarity and Communication Across a Platinum Metal Center

Ambient‐temperature photolysis of the aminoborylene complex [(OC)₅Cr?B?N(SiMe₃)₂] in the presence of a series of trans‐bis(alkynyl)platinum(II) precursors of the type trans‐[Pt(CCAr)₂(PEt₃)₂] (Ar=Ph, p‐C₆H₄OMe, and p‐C₆H₄CF₃) successfully leads to twofold transfer of the borylene moiety [ : B?N(SiMe₃)₂] onto the alkyne functionalities. The alkynyl precursors and resultant bis(borirene)platinum(II) complexes formed are of the type trans‐[Pt(B{?N(SiMe₃)₂}C?CAr)₂(PEt₃)₂] (Ar=Ph, p‐C₆H₄OMe, and p‐C₆H₄CF₃). These species have all been successfully characterized by NMR, IR, and UV/Vis spectroscopy as well as by elemental analysis. Single‐crystal X‐ray diffraction has verified that these trans‐bis(borirene)platinum(II) complexes display coplanarity between the twin three‐membered rings across the platinum core in the solid state and stand as the first examples of coplanar conformations of twin borirene systems. These complexes were modeled using density functional theory (DFT), providing information helpful in determining the ability of the transition metal core to interact with each individual borirene ring system and allowing for the observed coplanarity of these rings in the solid state. This proposed transition metal interaction with the twin borirene systems is manifested in the electronic characterization of these borirene species, which display divergent photophysical UV/Vis spectroscopic profiles compared to a previously published mono(borirene)platinum(II) complex.     

Bildung siliciumorganischer Verbindungen. 105. Reaktionen des (Cl3Si)2CPMe2Cl mit Silylphosphanen

Formation of Organosilicon Compounds. 105. Reactions of (Cl₃Si)₂C?PMe₂Cl with Silylphosphanes The reaction of (Cl₃Si)₂C?PMe₂Cl 1 with MeP(SiMe₃)₂ proceeds at 130°C (15 hrs.), by cleavage of all Si? P bonds to compounds 2, 3, 4, 5 . The course of this reaction incorporates a number of stages of which the compounds (Cl₃Si)₂C? PMe₂? P(Me)SiMe₃, (Cl₃Si)₂C?PMe₂? PMe? P(Me)SiMe₃ and ClP(Me)SiMe₃ are important and are yet to be isolated. The reaction of (Cl₃Si)₂C?PMe₂Cl with LiP(SiMe₂)₂ produces compound 2 as well as p₂(SiMe₃)₄ and P(SiMe₃)₃. The formation of 2 can be explained by the initial formation of the intermediate (Cl₃Si)₂C?PMe₂? P(SiMe₂)₂ with reacts with 1 to produce 2 and (ClP(SiMe)₃)₂. The formation of P₂(SiMe₃)₄ is also explained by the reaction of ClP(SiMe₃)₂ with LiP(SiMe₃)₄. The reaction of (Cl₃Si)₂C?PMe₂C(H)PMe₂ at 130°C/15–20 hrs. is related to the formation of (Me₃Si)₂C(H)Pme₂ from corresponding Si-methylated phosphorylides with the exception that, at 0°C, this reaction goes to completion within a few minutes.     

Immobilization of Platinum(II) and Platinum(IV) Complexes on Oxidized Nanoporous Carbon Material and Evaluation of the Enthalpy of Adsorption

Physicochemical study of cis-[Pt(NH3)2Cl2] and cis-[Pt(NH₃)₂Cl₂(OH)₂] is carried out, and immobilization of platinum complexes on the nanoporous carbon substrate is investigated. The solubility of cis-[Pt(NH₃)₂Cl₂] in 1 M HCl solution is determined, and the average enthalpy of dissolution is calculated: Δ_solH° = 27.3 ± 0.9 kJ/mol. The batch capacity is determined experimentally for cis-[Pt(NH3)2Cl2] and cis- [Pt(NH₃)₂Cl₂(OH)₂] to be 32.9 mg/g (0.17 mg-equiv/g) and 47.6 mg/g (0.24 mg-equiv/g), respectively. Immobilization of platinum complexes on the oxidized carbon surface is found to take place due to interaction between carboxy groups and ammine groups of platinum complexes. The resulting heat capacity curves are used to calculate the enthalpies of adsorption for cis-[Pt(NH₃)₂Cl₂] and cis-[Pt(NH₃)₂Cl₂(OH)₂] on the oxidized carbon surface, equal to 24.46 and 27.46 kJ/mol, respectively.     

Structural characterization of a mixed-ligand complex of copper(II) with 1,10-phenanthroline and the <Emphasis Type="Italic">m</Emphasis>-aminobenzoate ion

A new copper(II) complex of 1,10-phenanthroline (C1₂H₈N₂) and the meta-aminobenzoate ion (m-amb; C₇H₆NO ₂ ^? ), having the formula Cu(C₁₂H₈N₂)(C₇H₆NO₂)Cl?0.5H₂O, is prepared and characterized by elemental analysis, IR spectroscopy, and single crystal X-ray diffraction. The structure is built up from monomeric units in which the coordination environment around the metal ion is a square plane arising from a bidentate 1,10-phenanthroline molecule, a monodentate m-amb anion, and a chloride ion. A very long (Cu–N = 2.856(5) Å) bond to the nitrogen atom of an adjacent m-amb ion generates [101] polymeric chains in the crystal. The crystal structure is consolidated by N–H???O and O–H???O hydrogen bonds and C–H???O, C–H???Cl, and aromatic π–π stacking interactions. Crystal data: C₁₉H₁₅ClCuN₃O_2.5, M _r = 424.33, monoclinic, P2₁/n (No. 14), a = 9.8200(5) Å, b = 10.9291(7) Å, c = 16.3803(9) Å, β = 105.293(3)°, V = 1695.74(17) ų, Z = 4, R(F) = 0.043, wR(F ²) = 0.122.     

Alternative preparation and characterization of platinum(II) organometallic dinuclear complexes and oligomers with 3,8-diethynylphenanthroline derivatives

Novel platinum(II) organometallic dinuclear complexes and oligomers with two types of phenanthroline ligands, namely 3,8-diethynylphenanthroline (L1) and 3,8-bis-(4-ethynyl-phenylethynyl)-1,10-phenanthroline (L2), were synthesized from trans-Pt(PBu₃)₂(1-ethynyl-4-methyl-benzene)Cl and trans-Pt(PBu₃)₂Cl₂ by transmetalation of copper ion. The alternative procedure targeted platinum oligomer termination selection of either chloride or respective phenanthrolines and was successfully performed with different purifications by extraction and column chromatography. The structural formulae of these platinum complexes and oligomers were revealed with by analysis of both ³¹P{¹H}-NMR and ¹H-NMR spectral data. Alternative preparations of platinum oligomers with two types between chloride and respective phenanthroline termination are very useful for the selective synthesis for hybrid polymers with the coupling reaction with two different platinum oligomers with different diethynylaryl ligands. The platinum organometallic compounds showed similar absorption bands in the UV–Vis region. Those prepared with L1 had a strong absorption band at around 400 nm, assignable to the lowest energy metal-perturbed ¹[π–π*] transitions, while in compounds prepared with L2, the strong band appeared around 410 nm, because L2 has an extended π conjugation relative to L1. No distinct differences were observed in the absorption spectra of these platinum oligomers between the different terminal structures, chloride or various phenanthrolines. The luminescence spectra of the platinum compounds prepared with either L1 or L2, however, showed a distinct difference. Those with L1 showed only a phosphorescence assignable to a typical metal-perturbed ³[π–π*] transition with vibronic progressions centered at around 530 nm in deoxygenated CH₂Cl₂ at room temperature, while those with L2 showed weak dual emissions assignable to a mixture of typical metal-perturbed ¹[π–π*] and ³[π–π*] transitions in the visible region.     

Structure and thermal properties of a novel volatile bis(1,1,1-trifluoro-5,5-dimethyl-3-hexene-4-imino-2-onate) platinum(II) compound

A novel volatile Pt(II)β-iminoketonate complex is synthesized. β-Aminovinylketone H(i-ptac) = [CF₃–C(O)–CH=C(NH₂)–C(CH₃)₃] is used as a ligand. The XRD method is used to determine the structures of the ligand and the complex. The crystallographic data for C₁₆H₂₂F₆N₂O₂Pt are as follows: a = 10.0716(4) Å, b = 10.9572(4) Å, c = 9.6322(4) Å, β = 110.9010(10)°, space group С2/m, Z = 2, R = 0.011. The platinum atom has a square planar coordination with two oxygen and two nitrogen atoms of two bidentately linked ketoiminate ligands in trans-position; the PtO₂N₂ coordination site is formed.     

Synthesis,structure and electrochemical properties of some thiosemicarbazone complexes of iridium

Reaction of thiosemicarbazones of salicylaldehyde and 2-hydroxyacetophenone (H₂L¹ and H₂L²) with [Ir(PPh₃)₃Cl] affords complexes of type [Ir(PPh₃)₂(L)(H)] (L = L¹ or L²) in ethanol. A similar reaction carried out in toluene affords the [Ir(PPh₃)₂(L)(H)] complexes along with complexes of type [Ir(PPh₃)₂(L)Cl], where a chloride is coordinated to iridium instead of the hydride. The structure of the [Ir(PPh₃)₂(L²)(H)] and [Ir(PPh₃)₂(L²)Cl] complexes has been determined by X-ray crystallography. Crystal data for [Ir(PPh₃)₂(L²)(H)]: space group, P2₁/c; crystal system, monoclinic; a=12.110(2) Å, b=17.983(4) Å, c=18.437(4) Å, β=103.42(3)°, Z=4; R ₁=0.0591, wR ₂=0.1107. Crystal data for [Ir(PPh₃)₂(L²)Cl]: space group, P2₁/c; crystal system, monoclinic; a=17.9374(11) Å, b=19.2570(10) Å, c=24.9135(16) Å, β=108.145(5)°, Z=4; R ₁=0.0463, wR ₂=0.0901. In all the complexes the thiosemicarbazones are coordinated to the metal center as dianionic tridentate O, N, S-donors and the two triphenylphosphines are trans. The complexes are diamagnetic (low-spin d? ⁶, S=0) and show intense MLCT transitions in the visible region. Cyclic voltammetry on all the [Ir(PPh₃)₂(L)(H)] and [Ir(PPh₃)₂(L)Cl] complexes shows a quasi-reversible Ir(III)–Ir(IV) oxidation within 0.55–0.78 V vs. SCE followed by an irreversible oxidation of the thiosemicarbazone within 0.91–1.27 V vs. SCE. An irreversible reduction of the thiosemicarbazone is also observed within ?1.10 to ?1.23 V vs. SCE.     

Rare-earth metal dichloride and bis(alkyl) complexes containing amidinate-amidopyridinate ligands: synthesis,structure, and reactivity

A reaction of anhydrous yttrium chloride with an equimolar amount of lithium amidinateamidopyridinate obtained in situ by metallation of N,N’-bis(2,6-dimethylphenyl)-N-{6-[(2,6-dimethylphenyl)amino]pyridin-2-yl}acetimidamide ((2,6-Me₂C₆H₃)NH(2,6-C₆H₃N)N(2,6-Me₂C₆H₃)C(Me)=N(2,6-Me₂C₆H₃), L¹H) (1) with n-butyllithium in THF at–70 °C was used to synthesize the yttrium dichloride complex (L¹)YCl₂(THF)₂ (2). The lutetium bis(alkyl) complex, namely, N’-(2,6-diisopropylphenyl)-N-(2,6-dimethylphenyl-N-{6-[(2,6-dimethylphenyl)amido]pyridin-2-yl}acetimidoamidinatebis(trimethylsilylmethyl)lutetium (4), was obtained by the reaction of N’-(2,6-diisopropylphenyl)-N-(2,6-dimethylphenyl)-N-(6-((2,6dimethylphenyl)amino)pyridin-2-yl)acetimidamide ((2,6-Me₂C₆H₃)NH(2,6-C₆H₃N)N-(2,6-Me₂C₆H₃)C(Me)=N(2,6-Pr ₂ ⁱ C₆H₃), L²H (3)) with an equimolar amount of Lu(CH₂SiMe₃)₃(THF)₂. Complex 4 was found to be very stable and did not show indications of C—H-activation and other kinds of disintegration in benzene or toluene solution even upon prolonged heating at 60 °C. The reaction of complex 4 with an equimolar amount of 2,6-diisopropylaniline in toluene solution at room temperature led to the formation of the lutetium alkyl-anilide complex (L²)Lu(CH₂SiMe₃)(NH-2,6-Pr ₂ ⁱ C₆H₃) (5). A three-component system 4—AlBu ₃ ⁱ —[X][B(C₆F₅)₄] ([X] = [Ph₃C], [PhNHMe₂], the molar ratio of 1: 10: 1) was found to catalyze polymerization of isoprene.     

The Phase Diagram and the Application for the Quaternary System K+, $$ {\text{NH}}{_4^{+}} $$//Cl−, $$ {\text{SO}}{_4^{2 -}} $$SO42-–H2O at 80.0 °C

The solubilities in the quaternary system K⁺, \( {\text{NH}}{_4^{+}} \)//Cl^?, \( {\text{SO}}{_4^{2-}} \)–H₂O and its two ternary subsystems NH₄Cl–KCl–H₂O, (NH₄)₂SO₄–K₂SO₄–H₂O at 80.0 °C were measured using the isothermal dissolution equilibrium method under atmospheric pressure, and the corresponding phase diagrams were plotted. In the phase diagram of the NH₄Cl–KCl–H₂O system, there are three crystalline zones, which correspond to (K_1?m,(NH₄)_m)Cl, ((NH₄)_n,K_1?n)Cl and the co-existence zone of (K_1?m,(NH₄)_m)Cl and ((NH₄)_n,K_1?n)Cl, respectively. In the phase diagram of the (NH₄)₂SO₄–K₂SO₄–H₂O system, there is only one crystalline zone for (K_1?t,(NH₄)_t)₂SO₄. In the phase diagram of the K⁺, \( {\text{NH}}{_4^{+}} \)//Cl^?, \( {\text{SO}}{_4^{2-}} \)–H₂O system, there are three crystal zones, which correspond to (K_1?t,(NH₄)_t)₂SO₄, (K_1?m,(NH₄)_m)Cl and ((NH₄)_n,K_1?n)Cl, respectively. According to the analysis and the calculations for the phase diagrams of the K⁺, \( {\text{NH}}{_4^{+}} \)//Cl^?, \( {\text{SO}}{_4^{2 -}} \)–H₂O system at 80.0 °C and 50.0 °C, this paper proposes a technological process. In the process, the (K_1?t,(NH₄)_t)₂SO₄ can be prepared at 80.0 °C and the ((NH₄)_n,K_1?n)Cl can crystallize out at 50.0 °C. The mass fraction of K₂SO₄ in product L₁ (K_1?t,(NH₄)_t)₂SO₄ (t?=?0.1465) is 88.48%. The composition of solid solutions in the K⁺, \( {\text{NH}}{_4^{+}} \)//Cl^?, \( {\text{SO}}{_4^{2 -}} \)–H₂O system was experimentally determined and then theoretical calculations about the process can be carried out.     

Comparative reactivity of substituted 1,3-and 1,4-thiasilinane <Emphasis Type="Italic">S</Emphasis>-oxides in the sila-Pummerer rearrangement and inversion of the thiocarbonyl group

The thermal sila-Pummerer rearrangement of diastereomeric 2,3,3-trimethyl-1,3-thiasilinane S-oxides was studied. Introduction of the methyl group in the 2 position of 3,3-trimethyl-3-thiasilinane S-oxide slows down the rearrangement. When heated in CCl₄, the trans isomer (2-Me_eq, SO_eq) converts into the cis isomer (2-Me_eq, SO_ax) which rapidly rearranges into 2,2,7-trimethyl-1,6,2-oxathiasilepane. On the contrary, the isomeric 2,4,4-trimethyl-1,4-thiasilinane S-oxide is thermally stable up to 160°C in DMSO. The inversion at the sulfur atom in 2,3,3-trimethyl-1,3-thiasilinane S-oxides and 2,4,4-trimethyl-1,4-thiasilinane S-oxides under the action of triethyloxonium tetrafluoroborate was studied. The trans isomer of 2,3,3-trimethyl-1,3-thiasilinane S-oxide (2-Me_eq, SO_eq) forms with Et₃O⁺BF ₄ ^? a salt which decomposes in two ways. The first involves recovery of the starting sulfoxide due to Sn2 substitution at the carbon atom of the ethoxy group, and the second, convertion into the cis isomer (2-Me_eq, SO_ax) which rearranges into 2,2,7-trimethyl-1,6,2-oxathiasilepane. Under the same conditions, the cis isomer of 2,3,3-trimethyl-1,3-thiasilinane S-oxide (2-Me_eq, SO_eq) decomposes to form siloxanes. trans-2,4,4-Trimethyl-4-thiasilinane S-oxide (2-Me_eq, SO_eq) under the action of Et₃O⁺BF ₄ ^? convers into the cis isomer (2-Me_eq, SO_ax). The B3LYP/6-311G(d,p) theoretical analysis showed that the thermal inversion at the sulfur atom in the compounds studied has a high energy barrier.     

Crystal structure of [Ir(NH<Subscript>3</Subscript>)<Subscript>5</Subscript>Cl]<Subscript>2</Subscript>[OsCl<Subscript>6</Subscript>]Cl<Subscript>2</Subscript>. Crystal-chemical analysis of the iridium-osmium system

The [Ir(NH₃)₅Cl]₂[OsCl₆]Cl₂ binary complex salt has been prepared, and its structure was investigated by single crystal X-ray diffraction. Crystal data: a = 11.1901(13) Å, b = 7.9138(13) Å, c = 13.4384(18) Å; β = 99.640(3)°, V = 1190.0(2), space group C2/m, Z = 2, FW = 1099.47, d _x = 3.068 g/cm³. Thermolysis products of [Ir(NH₃)₅Cl]₂[OsCl₆]Cl₂, [Ir(NH₃)₅Cl][OsBr₆], (NH₄)₂[OsCl₆]_x[IrCl₆]_1?x , and K₂[OsCl₆]_x[IrCl₆]_1?x were studied by X-ray phase analysis; the unit cell parameters were refined, and the dependence of volume per atom (V/Z) on the composition of the Ir Os_1?x solid solution has been plotted.     

Crystal and molecular structures of the copper dichloride complex with 1-isopropenylimidazole

Crystal and molecular structures of the [CuL₂Cl₂] complex (L is 1-isopropenylimidazole) (I) are determined (R = 0.038, (wR ₂ = 0.092 for 2026 reflections with F _o ≥ 4σ(F _o); R ₁ = 0.123, wR ₂ = 0.117 for all reflections)) and compared with the structure of the known cobalt complex of analogous composition [CoL₂Cl₂] (II). Unlike complex II with the usual tetrahedral environment of the cobalt atom, the structure of the coordination polyhedron of the copper atom in compound I is intermediate between tetrahedron and square (the average dihedral angle between the ClCuN planes is 35.9°, and the ClCuCl (147.5°) and NCuN (163.1°) angles are much larger than the ClCuN angle of 90.1°–93.1°). The Cu-N (1.975(3), 1.959(3) Å) and Cu-Cl bonds (2.291(1), 2.278(1) Å) in complex I are typical of the copper(II) compounds. Different spatial structures of the 1-alkenylimidazole cycles in complexes I and II are found. Different short intermolecular contacts in crystals of compounds I (Cu…Cl, Cu…H) and II (Cl…C) result in the formation of chains with different mutual arrangements of molecules of the complexes.     

Structural and electronic properties of heptachlor

In this work, the molecular geometry of heptachlor is investigated using ab initio HF, DFT, LDA, and GGA methods. The natural bond orbital (NBO) analysis is performed at the B3LYP/6-311++G(d,p) level of theory. The first order hyperpolarizability β_total, the mean polarizability Δα, the anisotropy of the polarizability Δα, and the dipole moment μ, are calculated by B3LYP/6-311++G(d,p) and HF/6- 311++G(d,p) methods. The first order hyperpolarizability (β_total) is calculated based on the finite field approach. UV spectral parameters along with HOMO, LUMO energies for heptachlor are determined in vacuum and the solvent phase using HF, DFT, and TD-DFT/B3LYP methods implemented with the 6-311++G(d,p) basis set. Atomic charges and electron density of heptachlor in vacuum and ethanol are calculated using DFT/B3LYP and TD-DFT/B3LYP methods and the 6-311++G(d,p) basis set. In addition, after the frontier molecular orbitals (FMOs), the molecular electrostatic potential (MEP), the electrostatic potential (ESP), the electron density (ED), and the solvent accessible surface of heptachlor are visualized as a results of the B3LYP/6-311++G(d,p) calculation. Densities of states (DOS), the external electric field (EF) effect on the HOMO-LUMO gap, and the dipole moment are investigated by LDA and GGA methods.     

Hirshfeld Surface Analysis,Crystal Structure and Spectroscopic Studies of a New Cu(II) Halocuprate Salt with Protonated N-Amino-Ethyl-Piperazine

(C₆H₁₈N₃)₄[CuCl₅]₂[CuCl₄]₃·1.42H₂O is prepared and characterized by various physicochemical techniques. The single crystal X-ray diffraction structural analysis reveals that the title compound belongs to the orthorhombic system with the space group Cmca. Its unit cell dimensions are: a = 24.286(2) Å, b = 14.3082(14) Å, c = 16.6160(16) Å, Z = 4, V = 5773.8(10) ų. Its crystal structure is determined and refined down to R = 0.024 and wR(F²) = 0.059. The structure contains three crystallographically independent Cu²⁺ ions coordinated to chlorine anions in various fashions. Cu1 is five-coordinated in a distorted square pyramidal fashion, while Cu2 and Cu3 are four-coordinated in square planar and distorted tetrahedral fashions, respectively. The entities are interconnected by means of the hydrogen bonding [O(W)–H…Cl, N–H…Cl, C–H…Cl and C–H…O(W)], forming a three-dimensional network. Intermolecular interactions are investigated by Hirshfeld surfaces and the contacts of the eight different chloride atoms are notably compared. The vibrational absorption bands are identified by infrared spectroscopy. The optical study is performed by UV-vis absorption.     

Reaction of transsilylation of <Emphasis Type="Italic">N</Emphasis>-methyl-<Emphasis Type="Italic">N</Emphasis>-trimethylsilylacetamide with silanes ClCH<Subscript>2</Subscript>SiR<Superscript>1</Superscript>R<Superscript>2</Superscript>Cl

The reaction of N-methyl-N-trimethylsilylacetamide with silanes ClCH₂SiR¹R²Cl (R¹, R² = H, Me; H, Ph; Ph₂) leads to the formation of (O→Si) chelate compounds with pentacoordinate silicon: N-[chloro(methyl)-silyl]methyl-, N-[chloro(phenyl)silyl]methyl-, and N-[chloro(diphenyl)silyl]methyl-N-methylacetamides. From the data of multinuclear NMR spectroscopy, the intermediates of the reaction of N-methyl-N-trimethylsilylacetamide with ClCH₂SiPhHCl and ClCH₂SiPh²Cl are stable in CDCl₃ solution at room temperature during several days and slowly rearrange to the final (O–Si) chelate compounds.     

Bildung siliciumorganischer Verbindungen. 98. Umsetzung silylierter Phosphorylide mit PCl3

Formation of Organosilicon Compounds. 98. Reaction of Silylated Phosphorus Ylides with PCl₃ The reaction of Si-substituted phosphorus ylides as Me₂Si(CH₂? SiMe₂)₂C?PMe₃Br 1 , Cl₂Si(CH₂? SiCl₂)₂C?PMe₂Cl 2 , and (Cl₃Si)₂C?PMe₂Cl 3 with PCl₃ yields (Cl₂P)₂C?PMe₂Cl 5 by chlorinating cleavage of the Si-ylid-C bond. Besides 5 also (ClMe₂SiCH₂)₂SiMe₂, (Cl₃SiCH₂)₂SiCl₂, resp. SiCl₄ result from the reaction of 1, 2 and 3 with PCl₃. (Cl₂P)₂C?PMe₂Cl forms colourless crystals, mp. 84°C.