Half-sandwich complexes of lanthanides with tridentate ligands [RCH2CH(O)CH2OBun]2– (R = C5H4, 1-C9H6): synthesis,structures, and properties. The crystal structure of the complex {[(η5-C5H4)CH2CH(μ2:η1-O)CH2OBun]LaN(SiMe3)2}2

The oxirane-ring opening of butyl glycidyl ether with cyclopentadienylsodium or indenylsodium afforded cyclopentadienyl- and indenyl-substituted alcohols RHCH₂CH(OH)CH₂OBuⁿ (R = C₅H₄ (1) or 3-C₉H₆ (2), respectively), which were used as tridentate ligands. The reactions of these compounds with Ln[N(SiMe₃)₂]₃ produced the lanthanide complexes {[(⁵-R)CH₂CH(²:¹-O)CH₂OBuⁿ]LnN(SiMe₃)₂}₂ (R = C₅H₄, Ln = La (3), Pr (4), Er (5), Lu (6); or R = 1-C₉H₆, Ln = La (7)). The coordination spheres of the metal atoms in these complexes involve simultaneously the ⁵-cyclopentadienyl (indenyl), bridging alkoxide, and terminal amide ligands. The complexes were characterized by microanalysis, IR and NMR spectroscopy, and magnetochemistry. The crystal and molecular structure of complex 3 was established by single-crystal X-ray diffraction analysis.     

螺桨烷型分子BX[(CH_2)_n]_3和BX(CH_2)[CH(CH_2)_nCH](X=N,P)的结构和性质

采用密度泛函理论(DFT)研究了螺桨烷型分子BX[(CH2)n]3和BX(CH2)[CH(CH2)n CH](X=N,P;n=1-6)的结构、稳定性、化学键和电子光谱性质.计算结果表明这些分子都是稳定的.BX[(CH2)n]3(X=N,P;n=1-6)的最高占据分子轨道(HOMO)和最低空分子轨道(LUMO)之间的能隙均大于5.20 eV,其中BN[CH2]3和BP[CH2]3的能隙超过7.0 eV,与C5H6的能隙(7.27 eV)很接近,BX(CH2)[CH(CH2)n CH](X=N,P;n=1-6)的能隙在6.80 eV左右.所研究分子能量的二阶差分表明BN[(CH2)3]3、BP[(CH2)4]3及BX(CH2)[CH(CH2)2CH](X=N,P)是最稳定的.BX[(CH2)n]3的Wiberg键级表明除了BN[(CH2)n]3(n=2和6)中不存在B―N键,其它化合物中B和N均形成了化学键,BP[(CH2)n]3中除了BP[(CH2)2]3不存在B―P键,其它的均存在.电子密度的拓扑分析表明N―B键属于离子键,而P―B键具有共价键特征.BX[(CH2)n]3(X=N,P)的第一垂直激发能分别在191.1-284.8 nm和191.8-270.1 nm之间,BX(CH2)[CH(CH2)n CH](X=N,P)的第一垂直激发能分别在190.5-199.7 nm和209.0-221.3 nm之间.     

THE REACTIONS OF [MoCl(GeCl3)(CO)3(NCMe)2] WITH NEUTRAL BI- AND TERDENTATE DONOR LIGANDS

Abstract

The reaction of [MoCl(GeCl₃)(CO)₃(NCMe)₂] with an equimolar quantity of L?L {L?L = 2,2′-bipy, 1,10-phen, Ph₂P(CH₂)_nPPh₂ (n = 1 or 2)} in CH₂Cl₂ at room temperature gave either [MoCl(GeCl₃)(CO)₃(L?L)] (L?L = 2,2′-bipy or 1,10-phen) (1 and 2) or [MoCl(GeCl₃)(CO)₂ (NCMe)(L?L)]{L?L = Ph₂P(CH₂)_nPPh₂ (n = 1 or 2) (3 or 4), respectively. Equimolar quantities of [MoCl(GeCl₃)(CO)₂(NCMe){Ph₂P(CH₂)PPh₂}] (3) and L?L {L?L = 2,2′-bipy or Ph₂P(CH)₂PPh₂} react in CH₂Cl₂ at room temperature to afford the cationic complexes [Mo(GeCl₃)(CO)₂{Ph₂P(CH₂) PPh₂}(L?L)]Cl (5 and 6) in good yield. The cationic nature of 6 was established by chloride exchange by reacting Na[BPh₄] with 6 in acetonitrile to give the tetraphenylborate complex [Mo(GeCl₃)(CO)₂{Ph₂P(CH₂)PPh₂}₂][BPh₄] (7). Reaction of equimolar quantities of [MoCl(GeCl₃) (CO)₃(NCMe)₂] and PhP(CH₂CH₂PPh₂)₂ in CH₂Cl₂ at room temperature afforded the dicarbonyl complex [MoCl(GeCl₃)(CO)₂{PhP(CH₂CH₂PPh₂)₂}] (8) in good yield.     

Preparation & Stereochemistry of some Diphosphorus Heterocycles

Abstract

Cleavage of Ph₂P(CH₂)nPPh₂(n=2?5) with Li in THF provides a convenient source of the corresponding dianions which may be alkylated with X(CH₂)_nX (X=Cl,Br,n=1?3) to give diphosphorus heterocycles with a ring size 5–7. These are separated into their stereoisomers and stereochemical assignments made. An alternative route to an eight-membered ring is described.     

REACTIONS OF A PHOSPHORANIMINE ANION WITH SOME ORGANIC ELECTROPHILES

Abstract

The reactions of a variety of electrophiles with the N-silyl-P-trifluoroethoxyphosphoranimine anion Me₃Sin°P(Me)(OCH₂CF₃)CH^? ₂ (1a), prepared by the deprotonation of the dimethyl precursor Me₃SiN[dbnd]P(OCH₂CF₃)Me₂ (1) with n-BuLi in Et₂O at-78°C, were studied. Thus, treatment of 1a with alkyl halides, ethyl chloroformate, or bromine afforded the new N-silylphosphoranimine derivatives Me₃SiN[dbnd]P(Me)(OCH₂CF₃)CH₂R [2: R = Me, 3: R = CH₂Ph, 4: R = CH[sbnd]CH₂, 5: R = C(O)OEt, and 6: R = Br]. In another series, when 1a was allowed to react with various carbonyl compounds, 1,2-addition of the anion to the carbonyl group was observed. Quenching with Me₃SiCl gave the O-silylated products Me₃SiN[dbnd]P(Me)(OCH₂CF₃)CH₂°C(OSiMe₃)R¹R² [7: R ¹ = R ² = Me; 8: R ¹ = Me, R ² = Ph; 9: R¹ = Me, R ² = CH[sbnd]CH₂; and 10: R ¹ = H, R ² = Ph]. Compounds 2–10 were obtained as distillable, thermally stable liquids and were characterized by NMR spectroscopy (¹H, ¹³C, and ³¹P) and elemental analysis.     

ORGANISCHE PHOSPHORVERBINDUNGEN 86.1 HERSTELLUNG UND EIGENSCHAFTEN VON ω-PHOSPHINYL-α-AMINOALKYL-CARBONSÄUREN

Abstract

The synthesis, chemical and spectral properties of ω-methylphosphinyl-α-aminoalkylcarbonic acids, CH₃ (HO)P(O)(CH₂)_n CH(NH₂)CO₂H, n=3, 4, 5 or 6, are described. In contrast to the corresponding phosphonic acid derivatives these compounds exhibit no anticonvulsive and NMDA-antagonistic properties.     

The reactions of cyclotriphosphazene with 2-(2-hydroxyethylamino)ethanol. Spectroscopic studies of the derived products

Abstract

The reactions of cyclotriphosphazene (1) with 2-(2-hydroxyethylamino)-ethanol (2) were investigated. 2-(2-hydroxyethylamino)-ethanol (2) is a tri-functional reagent consisting of both aliphatic hydroxyl and the secondary amino groups and its nucleophilic substitution reactions with cylotriphosphazene can lead to different product types; open chain, spiro, ansa, bridged and their mixtures. The reactions with one, two and three equimolar ratios of 2-(2-hydroxyethylamino)-ethanol, in the presence of NaH at 0–10?°C and at room temperature gave the following cyclotriphosphazene derivatives: one mono-spiro, N₃P₃Cl₄[O–(CH₂)₂–NH–(CH₂)₂–O] (3, 1:1, r.t.); its isomer mono-ansa (5, 1:1, r.t.); one dispiro, N₃P₃Cl₂[O–(CH₂)₂–NH–(CH₂)₂–O]₂ (4, 1:1, r.t.); its isomer spiro-ansa (6, 1:2, r.t.); and one single-bridged compound with spiro substituted units, N₃P₃Cl₃[O–(CH₂)₂–NH–(CH₂)₂–O]₃N₃P₃Cl₃ (7, 1:3, at 0–10?°C); as well as single-, N₃P₃Cl₅[O–(CH₂)₂–NH–(CH₂)₂–O]N₃P₃Cl₅ (8, 1:2, r.t.), double-, N₃P₃Cl₄[O–(CH₂)₂–NH–(CH₂)₂–O]₂N₃P₃Cl₄ (9, 1:2, r.t.), and tri-bridged, N₃P₃Cl₃[O–(CH₂)₂–NH–(CH₂)₂–O]₃N₃P₃Cl₃ (10, 1:3, at 0–10?°C) derivatives. Triple-bridged derivative is the major product in this system. The structures of the novel-derived compounds were characterized by TLC-MS, FT-IR, elemental analysis, ¹H, and ³¹P NMR spectral.     

Neutral six-coordinate fluoro-phosphorus compounds

Abstract

Three new six-coordinate trifluoromethylfluorophosphorus carbamates F_4-n(CF₃)_nPO₂CN(CH₃)₂ (n = 1, 2, 3) have been prepared by reaction of trimethylsilylcarbamate with the appropriate fluorophosphorane. All products appear to be six-coordinate as indicated by characteristic high field ³¹P nmr chemical shifts and in some cases are fluxional. Two isomers are observed in the nmr spectra of the compound with n = 1. Only one structure is formed in the n = 2 and 3 cases. The crystal and molecular structure of F(CF₃)₃PO₂CN(CH₃)₂ revealed a six-coordinate structure with the unique F in the plane containing the chelated carbamate.     

Zur solvensfreien Darstellung von Tetramethylammoniumsalzen: Synthese und Charakterisierung von [N(CH3)4]2[C2O4], [N(CH3)4][CO3(CH3)], [N(CH3)4][NO2], [N(CH3)4][CO2H] und [N(CH3)4][O2C(CH2)2CO2(CH3)]

Solvent-free Synthesis of Tetramethylammonium Salts: Synthesis and Characterization of [N(CH₃)₄]₂[C₂O₄], [N(CH₃)₄][CO₃CH₃], [N(CH₃)₄][NO₂], [N(CH₃)₄][CO₂H], and [N(CH₃)₄][O₂C(CH₂)₂CO₂CH₃] A general procedure to synthesize tetramethylammonium salts is presented. Several tetramethylammonium salts were prepared in a crystalline state by solvent-free reaction of trimethylamine and different methyl compounds at mild conditions: [N(CH₃)₄]₂[C₂O₄] (cubic; a = 1 114.8(3) pm), [N(CH₃)₄][CO₃CH₃] (P2₁/n; a = 813.64(3), b = 953.36(3), c = 1 131.3(4) pm, β = 90.03(1)°), [N(CH₃)₄][NO₂] (Pmmn; a = 821.2(4), b = 746.5(3), c = 551.5(2) pm), [N(CH₃)₄][CO₂H] (Pmmn; a = 792.8(7), b = 791.7(3), c = 563.3(4) pm) and [N(CH₃)₄][O₂C(CH₂)₂CO₂CH₃] (P2₁; a = 731.1(2), b = 826.4(3), c = 1 025.2(3) pm, β = 110.1(1)°). The tetramethylammonium salts were characterized by IR-spectroscopy and X-ray diffraction. The crystal structures of the methylcarbonate and the nitrite are described.     

Syntheses,characterizations and crystal structures of two new complexes, [Co2(CH2 =C(CH3)CO2)4(phen)2(H2O)2] and [Pb2(CH2 =C(CH3)CO2)4(phen)2]

Two new complexes, [Co₂(CH₂=C(CH₃)CO₂)₄(phen)₂(H₂O)₂] (1) and [Pb₂(CH₂=C(CH₃)CO₂)₄(phen)₂] (phen = 1,10-phenanthroline) (2), have been synthesized and structurally characterized by single crystal X-ray diffraction methods. There are two cocrystallized conformers of [Co(CH₂=C(CH₃)CO₂)₂(phen)(H₂O)] in the asymmetric unit of 1 with the Co atoms displaying similar coordination modes. In the asymmetric unit of 2, there exist two crystallographically independent [Pb(CH₂=C(CH₃)CO₂)₂(phen)] molecules with the Pb atoms showing completely different coordination geometries. Weak intermolecular interactions such as hydrogen bonding and π–π stacking are responsible for the supramolecular assembly and stabilization of the crystal structures of 1 and 2. The complexes are characterized by elemental analysis, IR spectra, and UV–Vis spectra. The fluorescent properties of 2 are also discussed.     

Synthesis and Crystal Structures of Two Zinc(II) Complexes with the Tripodal Ligand Tris(2-Benzimidazolymethyl)Amine

This article reports the synthesis and crystal structures of two new mononuclear Zinc(II) complexes, [Zn₂(NTB)₂(N₃)₂](NO₃)₂·2CH₃OH (1) and [Zn₂(NTB)₂(SCN)₂](NO₃)₂·2CH₃OH·H₂O (2). Complex 1 crystallizes in the triclinic system, space group P&1macr;, a=13.743(4), b=14.374(4), c=14.443(5) Å; α=77.053(5), β=81.824(5), γ=88.959(6)°; Z=2; R1=0.0418, wR2=0.0889. Complex 2 also crystallizes in the triclinic system, space group P&1macr;, a=12.203(10), b=14.430(12), c=18.541(15)Å; α=72.712(15), β=85.039(15), γ=73.610(14); Z=2; R1=0.0771, wR2=0.1288. In both cases the central zinc(II) metal ions are coordinated to the four nitrogen atoms of NTB and a nitrogen atom of N^- ₃(1) or SCN^-(2) to form distorted trigonal bipyramidal coordination spheres.     

Syntheses,characterization and crystal structures of two square-planar Ni(II) complexes with unsymmetrical tridentate Schiff base ligands and monodentate pseudohalides

Two new square-planar Ni(II) complexes, [NiL¹(NCS)] (1) and [NiL²(N₃)] (2) have been synthesized with the unsymmetrical tridentate Schiff base ligands [(CH₃)₂NCH₂CH₂N=C(CH₃)CH=C(OH)(C₆H₅)], L ¹ H, derived from benzoylacetone and 2-dimethylaminoethylamine and [(CH₃CH₂)₂NCH₂CH₂N=C(CH₃)CH=C(OH)(C₆H₅)], L ² H, derived from benzoylacetone and 2-diethylaminoethylamine, respectively. The complexes have been characterized by elemental analysis, FT-IR, UV-Vis spectroscopy, electrochemical and thermal methods (where applicable). Structures have been established by the single-crystal X-ray diffraction technique which reveals the discrete nature of the complexes in which the metal centers adopt a distorted square planar geometry. Coordination environments of the metal ions in the complexes are satisfied with two different unsymmetrical Schiff base ligands having similar N₂O donor sets and a terminal pseudohalide anion (thiocyanate for 1 and azide for 2).     

Coordinating Properties of Dipod and Tripod Phosphorus Ligands with Separated Donor and Acceptor Sites

Abstract

The coordinating properties of dipod and tripod phosphorus ligands L_I = R₂M′ (OCH₂PMe₂) _n(CH₂CH₂PMe₂) _2-n and L_II = RM′ (OCH₂PMe₂)_n(CH₂CH₂PMe₂)_3-n (M′ = Si, Ge) with separated donor and acceptor centres have been investigated using electron rich metal complex fragments, e. g. M(CO)_m, (M = Cr, MO, W), π-C₅H₅Co, RhCl(CO) or Ni(CO), as bonding partners.     

High-yield catalytic metathesis of alkenyl tosylates with applications in organic synthesis

Alkenyl tosylates of the type RCHCH(CH₂)_nOTs [RH, n=9; RH, n=7; and RCH₃(CH₂)₇, n=8] undergo metathesis using a WCl₆-Me₃SnCl catalyst system, producing difunctionalised alkenes of the type TsO(CH₂)_nCHCH(CH₂)_nOTs (n=7,8, and 9); examples of the use of these products in synthesis are presented.     

Characterization and Molecular Structure of Bis(Isopropyl Xanthate) Bis(1,10-Phenanthroline) Nickel(II): [Ni(phen)2(CH3)2CHOCSS](CH3)2CHOCSS

The crystal and molecular structure of the title compound, [Ni(phen)₂(CH₃)₂CHOCSS](CH₃)₂CHOCSS has been determined by X-ray diffraction. The brown crystal is triclinic of space group Pi, with parameters a = 11.790(2), b = 12.410(3), c = 12.680(3) Å, α = 92.49(3), β = 96.54(3), γ = 117.43(3)° and Z = 2. The compound contains a six-coordinate cation and an isopropyl xanthate anion (CH₃)₂CHOCSS^?, the central Ni atom is chelated by four nitrogen atoms of two phenanthroline ligands and two sulfur atoms of an isopropyl xanthate ligand. The TG data indicate that it decomposed completely at 734°C.     

RADICAL IONS 561,2 ONE-ELECTRON OXIDATION OF 1,2-DITHIETE DERIVATIVES

Abstract

Novel 1,2-dithiete derivatives R₂C₂S₂ with R = [sbnd]C(CH₃)₃ and [sbnd]C(CH₃)₂[sbnd]CH₂[sbnd]CH₂[sbnd]CH₂[sbnd]C(CH₃)₂[sbnd] are readily oxidized by the one-electron transfer system AlCl₃/H₂CCl₂ to their radical cations. The single line ESR spectra, on high amplification, exhibit ³³S satellites in natural abundance. Both the ESR data, i.e. rather large g values and ³³S hyperfine coupling constants as well as MNDO closed and open shell calculations for the parent molecule H₂C₂S₂ illustrate that spin and positive charge are predominantly located in the SS bridge of the four-membered ring.     

Catalytic hydrogen transfer over magnesia, IXa. reduction of long chain aliphatic ketones by 2-propanol

A series of symmetrical long chain aliphatic ketones of general formula CH₃−(CH₂)_n-CO-(CH₂)₂−CH₃, where n=4,5,6,7 and 8, has been used as hydrogen acceptors from 2-propanol at 573–723 K in the presence of MgO catalyst under flow conditions. The yeilds of the appropriate alcohols exceeded 50%. Above 623 K the consecutive dehydration of the alcohols formed took place with moderate yields leading to internal alkenes. The direct one-step synthesis of C₁₃ alkene from 7-tridecanone has been realized under catalytic transfer reduction (CTR) conditions with high yield (>90%) over a MgO catalyst of enhanced acidity. Part VIII: Appl. Catal. A.:General,150, 77 (1997)     

Hydrosilylation of unsaturated compounds with 5-dimethylsilylfurfural diethyl acetal

Hydrosilylation of terminal acetylenes, HC≡CR (R = CMe₃,n-C₇H₁₅, SiMe₃, Ph, COOEt, CH₂N(CH₂)₄, and CH₂N(CH₂)₅) with 5-dimethylsilylfurfural diethyl acetal (1) gives a mixture of products of bothtrans-β- and α-addition. When R = CMe₃ or SiMe₃, the reaction proceeds regio- and stereospecifically to give only thetrans-β-derivatives. The formation of β-adducts is favored by pronounced electron-donating substituents and steric hindrance at the C_α atom. Terminal alkenes, H₂C=CHR (R = CH₂CN, CH₂N(CH₂)₄, CH₂N(CH₂)₅, SiMe₃, SiMe(α-furyl)₂, SiMe₂(α-furyl), SiMe₂(α-thienyl), and SiMe₂(5-chloro-2-thienyl)), react with silane1 to give only the products of β-addition; the reaction of1 with H₂C=CHCH₂NHC₆H₁₃-n affords a mixture of β- and α-adducts in a ratio of 1.8∶1. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1784–1788, October, 1993.     

ALKALI-PHOSPHORVERBINDUNGEN UND IHR REAKTIVES VERHALTEN LXXIV Synthese und Reaktionsverhalten von Alkylen-bis-alkylphosphinen

Abstract

Alkylen-bis-phosphine H₂P-(CH₂)nPH₂ (n=2, 3, 4) lassen sich unter geeigneten Bedingungen zu H(M)P-(CH₂ n- PH₂ und H(M)P-(CH₂)n-P(M)H metallieren und nach Umsatz mit Alkylhalogeniden in die entsprechenden Phosphine HRP-(CH₂)n-PH₂ sowie HRP-(CH₂)n-PRH überführen. Letztere sowie deren Alkaliphosphide sind Ausgangabasis für die Synthese von P-E-P-Heterocyclen (E=Mg, C, Si, Ge) mit 5, 6 und 7-Ringstruktur. Der Reaktionsverlauf zwischen BuLiP-(CH₂)₃-PLiBu und CH₂C1₂ wird diskutiert. Die Struktur der dargestellten Verbindungen wird NMR- und massenspektrokopisch gesichert.

The metallation of alkylen-bis-phosphines H₂P-(CH₂)nPH₂ (n=2, 3, 4) under suitable conditions leads to H(M)P-(CH₂)n-PH₂ and H(M)P-(CH₂)n-P(M)H which reacts with alkylhalides forming the corresponding phosphines. The latter and their alkaliphosphides, respectively, are suitable materials to prepare P-E-P-heterocycles (E=Mg, C, Si, Ge) of 5, 6 and 7-ring structure. The structure of the synthesized compounds is elucidated by investigation of their mass and ³¹P-nmr-spectra.