Preparation of Copolymer of Salen-crown Ether Complexes and its Catalytic Activation for Molecular Oxygen

A new stable salen Schiff base cobalt and crown ether sodium complex （SalCo-NaB18C6） was prepared through copolymerization. This copolymer complex was applied to catalytic oxidation of hydrocarbon compound with molecular oxygen without reductant, which was shown the higher activity and selectivity for ketone, and reused effectively.

Two-dimensional Network Crown Ether Complex. Synthesis and Crystal Structure of 18-Crown-6 Complex: [K(18-C-6)]_2[Cd-(mnt)_2]

The novel complex [K(18-C-6)]_2 [Cd(mnt)_2] [18-C-6 = 18-crown-6, mnt =1,2-dicyanoethene-1,2-dithiolate, C_2S_2-(CN)_2^(2-)] was synthesized and characterized by elementalanalysis, IR spectrum and X-ray diffraction analysis. The complex displays two-dimensional networkstructure of [K(18-C-6)] complex segments and [Cd(mnt)_2] complex segment bridged by S-K-S, S-K-Nand N-K-N interactions between adjacent [K(18-C-6)] and [Cd(mnt)_2] units.

Studies on the Synthesis and Complexing Behavior of Crown Ethers with External Coordination Center

The synthesis, characterization of five ditopic or tritopic crown compounds were reported in this paper together with the preparation of the corresponding hetero-dinuclear and hetero-trinuclear complexes with different metal cations.

Studies on Rare Earth Complexes with Crown Ether (ⅩⅩⅣ)——Synthesis and Characterization of Complexes of Lanthanide Isothiocyanates with Dibenzo-30-crown-10

Introduction The study of metal complexes with the crown ether is a quite interesting research field, but the research has mainly focused on the metal complexes with some crown ethers with a relatively small cavity such as 12-crown-4, 15-crown-5 and 18- crown-6 as well as their derivatives. Crown ethers with a larger cavity contain more oxygen atoms, so they have the ability to form the complexes of a higher co-

SILICA-BOUND CROWN ETHERS PLATINUM COMPLEX AS HYDROSILYLATION CATALYST

Silica-bound 15-Crown-5, 18-Crown-6 with a spacer of propyloxymethyl and their platinum complexes have been synthesized. It was found that they were efficient catalysts for the hydrosilylation of olefms with triethoxysilane in the temperature range of 60 to 130 ℃.

NETWORK CROWN ETHER POLYMERS WITH CENTRIC FUNCTIONAL GROUP (Ⅳ) SYNTHESIS OF NETWORK CROWN ETHER POLYMER WITH PENDANT DIETHYLAMINO THIAALKYL GROUP AND ITS PLATINUM COMPLEX

The title polymer was prepared from 5-diethylamino-3-thia-pentyl glycidyl ether anddiethylene glycol bisglycidyl ether via ring-opening copolymerization. It was found that thisreaction could be catalyzed by sodium, but not Lewis acid. The obtained polymer can coordinatewith platinum compound, and the platinum complex is a new kind of catalyst for thehydrosilylation of olefins with triethoxysilane.

STUDIES ON RARE EARTH COMPLEXES WITH CROWN ETHERS ⅩⅧ——Synthesis,Characterization and Crystal Structure of[Sc(NO_3)_3(H_2O)_2]·(15-Crown-5)

The single crystal of the complex [Sc(NO_3)_3(H_2O)_2]·(15C5) has been prepared in acetonitrile.The new complex has been characterized by elemental analysis,IR spectra,solubility and molar conductance measurements.The structure of the complex is determined by single crystal X-ray diffraction analysis.

SPECTRAL STUDY ON A NEW 3d_z^2 TYPE COPPER(Ⅱ)COMPLEX OF PHENOLIC POLYMERIC CROWN ETHER

ESR and IR measurements have been carried out for a copper(Ⅱ)complex of phenolic polymeric crown ether,As a result,the triplet ESR spectrum(S=1)of 3d_z2 ground state copper(Ⅱ)ions was first observed for the powder sample.It indicated that there existed intramolecular spin-spin interaction betweeen 3d_Z2 ground state copper(Ⅱ)and copper(Ⅱ)ions.In this binuclear triplet cluster,the axial ligntion of one water molecule in a sandwich position to two adjacent copper(Ⅱ) ions was also confirmed by IR spectra,All things considered,a possible structure for the complex was proposed.

ELECTRONIC STRUCTURE AND BOND CHARACTER OF COMPLEXES OF RARE EARTH CHLORIDES WITH CROWN ETHERS

A series of lanthanide complexes LnCl_3·L(Ln=La,Pr,Nd;L=15-C-5 or 18-C-6)have been synthesized and their molecular configuration,electronic structure and bond character have been studied by XPS and quantum chemical calculation.The calculated results are in good agreement with that obtained in the experiments.Three Cl atoms are on the same side of Ln in LnCl_3·15-C-5 and the crown ring on the other side.forming a complex molecule with coordination number 8.LnCl_3·15-C-5 is easily hygroscopic in air because of its unsaturated coordination,which differs sharply from the stable Ln(NO_3)_3·15-C-5 com- plex of coordination number 11.The HOMO and neighboring occupied MOs are composed of Cl 3p and O2p, and the LUMO and neighboring unoccupied MOs are composed of Ln orbitals.The level structure easily pro- duces Ln3d satellite in XPS caused by L→Ln charge transfer transition.Due to the coordination,the absolute values of the charge are decreased at Ln and O atoms,but increased at Cl atoms,which is in agreement with XPS results.

STUDIES ON COMPLEXES OF RARE EARTHS WITH CROWN ETHERS(V)-SYNTHESIS AND CHARACTERIZATION OF THE COMPLEXES OF RARE EARTH NITRATES WITH 2,2'-DINITRO-4,5,4',5'-BIS-(15-CROWN-5)-DIBENZO DISULFIDE

Three new solid complexes of macrocyclic polyether ligand 2, 2'-dinitro-4, 5, 4', 5'bis-(15- crown-5)-dihenzo disulfide(L) with trivalent rare earth nitrates having composition of RE(NO_3)_3·L ·6H_2O(RE=Ce, Pr, Nd) have been synthesized in acetonitrile. All the isolated complexes have been characterized by elementary analysis, IR and UV spectra, differential thermal and thermogravimetric analysis, X-ray powder diffraction analysis, molar conductance and measurements of solubility in some general solvents.

STUDIES ON COMPLEXES OF RARE EARTHS WITH CROWN ETHERS(Ⅳ)SYNTHESIS AND CHARACTERIZATION OF THE COMPLEXES OF RARE EARTH NITRATES WITH 4'-BROMO-5'-NITROBENZO-15-CROWN-5

Six new solid complexes of macrocyclic polyether ligand 4′-bromo-5′-nitrobenzo-15-crown-5(L)with Uivalent rare earth nitrates having composition of RE(NO_3)_3·L·mCH_3CN·nH_2O(RE=L_a--Nd,m=n=0, RE=Sm,Bu,m=0.1,n=1,4)have been synthesized in acetonitrile or acetone.All the isolated complexes have been char- acterized by elementary analysis,IR and UV spectra,differential thermal and thermogravimetric analysis,X-ray powder diffraction analysis,molar conductance and measurementa of solubility in some general solventa.It shows that coordination number of the rare earth cation in the complexes of La,Ce,Pr and Nd nitrate is eleven.

Bibracchial Lariat Ethers(Ⅰ)——The Synthesis and Crystal Structure of the N,N'-bis(2-Methoxy-1-Naphthylmethyl)-4,13-Diaza-18-Crown-6 Sodium Iodide Complex

Diaza Crown ethers are versatile complexing reagents, their complexing abilities are dramatically modified by the electron donating atoms on substituents attached to the nitrogen if they can give a three-dimensional cavity as in cryptates. Hence the synthesis and characterization of bibracchial lariat ethers (BIBLES) have received much attention. In the preparation of new BIBLES, a complex Ⅱ was unexpectedly obtained.

Crystal Structures of Ln(NO_3)_3(Ln=La,Yb) Complexes with 12-crown-4

The synthesis and crystal structures of Ln(NO3)3(Ln=La,Yb) complexes with 12-crown-4 are reported. La (NO3 )3 (12-crown-4) (H2O)x(Ln=La,x=1; Ln=Yb, x=0), Mr=519. 2(535.3), space group P21/n(P21/c)with α =7. 612(2)(12. 116(3)), b=13. 932(6) (8. 544(3)),c= 16. 179(6) (15.241 (3));β=101.40 (2)( 91.82 (2))°; V=1682 (1) (1577(1)); Z=4 (4);μ(MoKα)=26.7(63.2) cm -1; F(000) =1024 (1036) ; R=0. 035 (0. 034) ; Rw= 0. 028 (0.036) for 1665 (1594) observed reflections with Ⅰ>3σ(Ⅰ). The La(Ⅲ) ion in La (NO3)3 (12-crown-4) (H2O) is 11-coordinated, being bonded to three bidentate nitrate ions , four oxygen atoms of the crown molecule and one oxygen atom of a water molecule. Yb(NO3)3 (12-crown-4) is a 10-coordinated complex, in which the metal ion bonds with three bidentate nitrate ions and four oxygen atoms of a crown ether.

The Novel Benzo-15-Crown-5 with Palladium(II) Complex: [Na(B15CS)]_2,[Pd(SCN)_4]

A novel Pd(II) Benzo-15-crown-5 complex [Na(B15CS)]_2[Pd(SCN)_4] has been isolated and characterized by IR and X-ray diffraction analysis. The crystal structure belongs to monoclinic, space group P2_1,/n with cell dimensions, a = l.0164(6), b = l.3743(3), c = l.4987(7) nm, β = 95.248(6) °, V = 2.0847 'nm_3, Z = 2, F(000) = 944, R = 0.053, Rw = 0.072. The compound consists of two [Na(B15CS)]+ complex canons and a [Pd(SCN)4_]^(2-) complex anion. Each sodium ion is coordinated by five crown ether oxygen atoms and one N atom from the SCN group of [Pd(SCN)_4]^(2-) to form stable neutral complex.

Synthesis and Properties of New-type Troponoid Dithio-Crown Ethers

Condensation of 3,7-dichloromethyl-5-isopropyl-2-methoxytropane 4 with bis (mercaptoethyl) ether 5a and mono, di, and tri-ethylene glycol bis(mercaptoethyl) ethers 5b-5d gave troponoid-annexed dithiocrown ethers 6a-6d. Compounds 6a-6d have selective and reversible mercury salt capturing ability.

Calorimetric Titration of Complexation of the N-benzylmonoaza-18-Crown-6 with Rare Earth(Ⅲ)Nitrates in Anhydrous Acetonitrile

Calorimetric titrations were performed in anhydrous acetonitrile at 298.15 K,giving the com-plex stability constants(K_s)and the thermodynamic parameters for the complexation of the rare earth ni-trates(La～Er,Yb)with N-benzylmonoaza-18-crown-6(18-C-6).Thermodynamic quantities clearly in-dicate that the coordination stability of the arm-type 18-crown-6 with the lanthanoid nitrates increasesfrom Ce to Gd,and decreases slightly from Gd to Tb with increasing atomic number.The coordination of thearm-type 18-C-6 with Gd shows the stonger complexation ability and selectivity.Thermodynamically theformation of the complexes is evidently driven by enthalpy,but the complexes stability sequence is essentiallyentropy governed.

CROWN FUNCTIONALIZED LINEAR POLYSILOXANE PLATINUM COMPLEX AS HYDROSILYLATION CATALYST

A modified method of preparing crown functionalized linear polysiloxane has been described.4'-allylbenzo-15-crown-5 was subjected to hydrosilylation with methyldichlorosilane,followed bypolycondensation with silanol-terminated polydimethylsiloxane to give the title crownfunctionalized linear polysiloxane. It was found that the polysiloxane could be coordinated withplatinum salt to form platinum complex, which could catalyze the hydrosilylation of olefins withtriethoxysilane efficiently.

Studies On A Selena-aza-crown Ether: Synthesis and Catalytic Behavior In Hydrosilylation

The synthesis of a new type of selena aza crown ether 6 (4 nitrobenzyl) 1,4,7,10 selenatriazacyclododecane (L) derivated from phenylalanine , and its platinum(Ⅱ) complex was described. The catalytic activity of this complex for the hydrosilylation of olefins by triethoxysilane was investigated.