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1.
Deacon GB Delbridge EE Evans DJ Harika R Junk PC Skelton BW White AH 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(5):1193-1204
Sodium and potassium tetrakis(3,5-di-tert-butylpyrazolato)lanthanoidate(III) complexes [M[Ln(tBu(2)pz)(4)]] have been prepared by reaction of anhydrous lanthanoid trihalides with alkali metal 3,5-di-tert-butylpyrazolates at 200-300 degrees C, and a 1,2,4,5-tetramethylbenzene flux for M=K. On extraction with toluene (or occasionally directly from the reaction tube) the following complexes were isolated: [Na(PhMe)[Ln(tBu(2)pz)(4)]] (1 Ln; 1 Ln=1 Tb, 1 Ho, 1 Er, 1 Yb), [K(PhMe)[Ln(tBu(2)pz)(4)]].2 PhMe (2 Ln; 2 Ln=2 La, 2 Sm, 2 Tb, 2 Ho, 2 Yb, 2 Lu), [Na[Ln(tBu(2)pz)(4)]](n) (3 Ln; 3 Ln=3 La, 3 Tb, 3 Ho, 3 Er, 3 Yb), [K[Ln(tBu(2)pz)(4)]](n) (4 Ln; 4 Ln=4 La, 4 Nd, 4 Sm, 4 Tb, 4 Ho, 4 Er, 4 Yb, 4 Lu), with the last two classes generally being obtained by loss of toluene from 1 Ln or 2 Ln, and [Na(tBu(2)pzH)[Ln(tBu(2)pz)(4)]].PhMe (5 Ln; 5 Ln=5 Nd, 5 Er, 5 Yb). Extraction with 1,2-dimethoxyethane (DME) after isolation of 2 Ho yielded [K(dme)[Ho(tBu(2)pz)(4)]] (6 Ho). X-ray crystal structures of 1 Ln (=1 Tb, 1 Ho; P2(1)/c), 2 Ln (=2 La, 2 Sm, 2 Tb, 2 Yb, 2 Lu; Pnma), 3,4 Ln (=3 La, 3 Er, 4 Sm; P2(1)/m), and 5 Ln (=5 Nd, 5 Er, and 5 Yb; P1) show each group to be isomorphous regardless of the size of the Ln(3+) ion. All complexes contain eight-coordinate [Ln(eta(2)-tBu(2)pz)(4)] units. These are further linked to the alkali metal by bridging through two (1,2,5 Ln) or three (3,4 Ln) tBu(2)pz groups which show striking coordination versatility. Sodium is coordinated by an eta(4)-PhMe, a micro-eta(2):eta(2)-tBu(2)pz, and a micro-eta(4)(Na):eta(2)(Ln)-tBu(2)pz ligand in 1 Ln, and by one eta(1)-tBu(2)pzH and two micro-eta(3)(Na):eta(2)(Ln) ligands in 5 Ln. By contrast, potassium has one eta(6)-PhMe and two micro-eta(5)(K):eta(2)(Ln) ligands in 2 Ln. Classes 3,4 Ln form polymeric chains with the alkali metal bonded by two micro-eta(3)(NNC-M):eta(2)(Ln)-tBu(2)pz ligands within [MLn(tBu(2)pz)(4)] units which are joined together by eta(1)(C)-tBu(2)pz-Na, K linkages. 相似文献
2.
Deacon GB Gitlits A Roesky PW Bürgstein MR Lim KC Skelton BW White AH 《Chemistry (Weinheim an der Bergstrasse, Germany)》2001,7(1):127-138
The homoleptic rare-earth pyrazolate complexes [Sc(tBu2pz)3], [Ln2(tBu2pz)6] (Ln = La, Nd, Sm, Lu), [Eu4(tBu2pz)8] and the mixed oxidation state species [Yb2(tBu2pz)5] (tBu2pz = 3,5-di-tert-butylpyrazolate) have been prepared by a simple reaction between the corresponding rare-earth metal and 3,5-di-tert-butylpyrazole, in the presence of mercury, at elevated temperatures. In addition, [Yb2(tBu2pz)6] was prepared by redox transmetallation/ligand exchange between ytterbium, diphenylmercury(II) and tBu2pzH in toluene, whilst the same reactants in toluene under different conditions or in diethyl ether gave [Yb2(tBu2pz)5]. The complexes of the trivalent lanthanoids display dimeric structures [Ln2(tBu2pz)6] (Ln = La, Nd, Yb, Lu) with chelating eta2-terminal and eta2:eta2-bridging pyrazolate coordination. The considerably smaller Sc3+ ion forms monomeric [Sc(tBu2pz)3] of putative D3h molecular symmetry, with pyrazolate ligands solely eta2-bonded. [Eu4(tBu2pz)8] is a structurally remarkable tetranuclear EuII complex with two types of europium centres in a linear array. The outer two are bonded to one terminal and two bridging pyrazolates, and the inner two are coordinated by four bridging ligands. Unprecedented mu-eta5:eta2 pyrazolate ligation is observed, with each outer Eu2+ sandwiched between two eta5-bonded pyrazolate groups, which are also eta2-linked to an inner Eu2+. The two inner Eu2+ ions are linked together by two equally occupied components of each of two symmetry related, disordered pyrazolate groups with one component eta4:eta2 bridging and one eta3:eta2 bridging. [La2(tBu2pz)6] has also been shown to be a Tishchenko reaction catalyst with several organic substrates. 相似文献
3.
Reaction of halogenobenzoic acids with bis(pentafluorophenyl)ytterbium(II) in tetrahydrofuran results in selective removal of halogen substituents. 相似文献
4.
5.
R.J. Bertino B.A.W. Coller G.B. Deacon I.K. Johnson 《Journal of fluorine chemistry》1975,5(4):335-357
The lithium polyfluorobenzenesulphinates, Li O2SR (R = C6F5, -HC6F4, -HC6F4, or -HC6F4), and the dilithium tetrafluorobenzenedisulphinates, - and -(LiO2S)2C6F4, have been prepared by reaction of the appropriate polyfluoroaryllithium compounds with sulphur dioxide. All compounds were isolated as hydrates and gave the corresponding -benzylthiouronium salts on treatment with -benzylthiouronium chloride. From reactions of the lithium sulphinates with suitable mercuric salts in water, generally at room temperature, the derivatives RHgX (R = C6F5, X = Cl, Br, CH3CO2, or PhSO2; R = -HC6F4, X = Cl, Br, or CH3CO2; R = -HC6F4, X = Cl or Br; R = -HC6F4, X = Cl), -(XHg)2C6F4 (X = Cl, Br, or CH3CO2), and -(XHg)2C6X4 (X = Cl or Br) have been prepared. Similarly, the bispolyfluorophenylmercurials R2Hg (R = C6F5, -HC6F4, or -HC6F4) have been prepared from the corresponding lithium sulphinates and either mercuric salts or polyfluorophenylmercuric halides in aqueous -butanol. A possible mechanism for the sulphur dioxide elimination reactions is discussed. 相似文献
6.
Summary The rhodium(I) carboxylates,trans-RhO2CR(CO)(PPh3)2 (R = C6F5, C6Cl5,p-HC6F4,m-HC6F4,o-HC6F4,p-McOC6F4, 4,5-H2C6F3, 3,5-H2C6F3, or 2,6-F2C6H3, have been prepared by reaction of RhH(CO)(PPh3)3 with the appropriate polyhalogenobenzoic acids in ethanol and/or by reaction oftrans-RhCl(CO)(PPh3)2 with the appropriate thallous carboxylates in benzene. Decarboxylations with formation of polyhalogenoarylrhodium(I) compounds,trans-RhR(CO)(PPh3)2 (R = C6F5, C6Cl5,p-HC6F4,m-HC6F4,p-MeOC6F4, 4,5-H2C6F3 or 3,5-H2C6F3), have been achieved either by decomposition of the corresponding rhodium(I) carboxylates in pyridine or by reaction oftrans-RhCl(CO)(PPh3)2 and the thallous carboxylates in pyridine, but the derivatives R =o-HC6F4 or 2,6-F2C6H3 could not be obtained by this method. The rate of decarboxylation decreased in the sequence R = C6F5 >p-MeOC6F4 >p-HC6F4 >m-HC6F4 > 4,5-H2C6F3 > 3,5-H2C6F3.Part 1, ref. 10.Preliminary communication, ref. 9. 相似文献
7.
Kepert CM Deacon GB Sahely N Spiccia L Fallon GD Skelton BW White AH 《Inorganic chemistry》2004,43(9):2818-2827
The reactions of bidentate diimine ligands (L2) with binuclear [Ru(L1)(CO)Cl2]2 complexes [L1 not equal to L2 = 2,2'-bipyridine (bpy), 4,4'-dimethyl-2,2'-bipyridine (4,4'-Me2bpy), 5,5'-dimethyl-2,2'-bipyridine (5,5'-Me2bpy), 1,10-phenanthroline (phen), 4,7-dimethyl-1,10-phenanthroline (4,7-Me2phen), 5,6-dimethyl-1,10-phenanthroline (5,6-Me2phen), di(2-pyridyl)ketone (dpk), di(2-pyridyl)amine (dpa)] result in cleavage of the dichloride bridge and the formation of cationic [Ru(L1)(L2)(CO)Cl]+ complexes. In addition to spectroscopic characterization, the structures of the [Ru(bpy)(phen)(CO)Cl]+, [Ru(4,4'-Me2bpy)(5,6-Me2phen)(CO)Cl]+ (as two polymorphs), [Ru(4,4'-Me2bpy)(4,7-Me2phen)(CO)Cl]+, [Ru(bpy)(dpa)(CO)Cl]+, [Ru(5,5'-Me2bpy)(dpa)(CO)Cl]+, [Ru(bpy)(dpk)(CO)Cl]+, and [Ru(4,4'-Me2bpy)(dpk)(CO)Cl]+ cations were confirmed by single crystal X-ray diffraction studies. In each case, the structurally characterized complex had the carbonyl ligand trans to a nitrogen from the incoming diimine ligand, these complexes corresponding to the main isomers isolated from the reaction mixtures. The synthesis of [Ru(4,4'-Me2bpy)(5,6-Me2bpy)(CO)(NO3)]+ from [Ru(4,4'-Me2bpy)(5,6-Me2bpy)(CO)Cl]+ and AgNO3 demonstrates that exchange of the chloro ligand can be achieved. 相似文献
8.
From a range of preparative methods, three geometric isomers of bis(diphenylarsino)methane‐dichloroplatinum(II) have been isolated, viz. cis‐PtCl2(dpam), trans, trans‐Pt2Cl4(dpam)2 and cis, trans‐Pt2Cl4(dpam)2. Their structures were determined by single‐crystal X‐ray diffraction. 相似文献
9.
The preparations, stabilities and structures of the complexes R2TlX and R2 LTlX (R = C6F5, p-HC6F4, or o-HC6F4; X = Br or Cl; L = Ph3PO, 2,2′-bipyridyl (bpy) or Ph3P) have been examined or (R = C6 F5) reinvestigated. The derivatives R2TlX are monomeric in acetone, from which the complex (p-HC6F4)2 Me2COTIBr has been isolated. In this solvent, the complexes R2LTlX (L = Ph3PO, bpy, or Ph3P) undergo partial dissociation by loss of L. When L = bpy, there is also slight ionization into R2LTl+ and R2TlX?2. The acceptor properties of R2TlX compounds towards uncharged ligands decrease R = C6F5 ? p-HC6F4 > o-HC6F4 > Ph. Dimeric behaviour is observed for R2TIX compounds in benzene, whilst R2LTlX (L = Ph3PO or bpy) derivatives show slight but significant association. In the solid state, R2TlX compounds are considered to be polymeric with five coordinate thallium, and R2LTlX derivatives to be dimeric with five (L = Ph3PO) or six (L = bpy) coordinate thallium by contrast with four coordinate dimeric and four or five coordinate monomeric structures previously proposed for the respective pentafluorophenyl derivatives. Halogen bridging is unsymmetrical for R = C6F5 or p-HC6F4, but may be more symmetrical for R = o-HC6F4 when L = Ph3PO or bpy. Reported structural data for the complexes (C6F5)LTlX (L = Ph3AsO, Ph3P, Ph3As, or 1,10-phenanthroline; X = Br or Cl) and (C6F5)2TlCl?2 are reinterpreted and the proposed structures revised. 相似文献
10.
Kim Henrick Mary McPartlin Glen B. Deacon Roderic J. Phillips 《Journal of organometallic chemistry》1980,204(3):287-294
An X-ray crystallographic study has shown that the complex (C6H5)2TlO2CC6F5(OPPh3) has a dimeric structure with unsymmetrical pentafluorobenzoate bridging (TlO 2.531 and 2.789 Å) but an exact crystallographic centre of symmetry. The pentafluorobenzoate groups are also unsymmetrically chelated to thallium (TlO 2.389 and 2.531 Å.), which overall has irregular six coordination. 相似文献