Tetrafluoroborate Complexes Research Articles

ChemInform Abstract: Preparation, Structure, and Properties of Manganese Toluene‐3,4‐dithiolate Complexes in Different Oxidation States.

AbstractThe anaerobic reaction shown in the scheme yields the tetrahedral Mn(II) complex (III) (space group P21/c, Z=4).

Preparation, structure, and properties of manganese toluene-3,4-dithiolate complexes in different oxidation states

in acetonitrile, a Hammett plot showed a linear relationship between Hammett u, values and the second reduction potential, indicating that electron density changes on the ligand are transmitted to the metal ions.'O Replacement of the 4-methyl ring substituent by CF3 in I and I1 has been shown to increase Elp for both one-electron-reduction steps in DMF by 0 . 1 4 4 1 9 V, clearly indicating the transmission of a distant electron-withdrawing effect to the copper centers. The wide separation of the two reduction waves of all these compounds indicates significant stability for the one-electron intermediates, as is indicated by the large conproportionation constants (Table VII). The one-electron-reduced species derived from I exhibits a seven-line EPR spectrum at room temperature in both CH2C12 and CH3CN, indicative of interaction of the odd electron with both copper Compound I1 produces a one-electron-reduced species in CH3CN, which also exhibits a seven-line spectrum (Figure 6). The analogous copper tetrafluoroborate complex involving the butylene-bridged macrocyclic ligand derived from 4-tert-butyl-2,6-diformylphenol has also been shown to produce a one-electron-reduced species in CH2C12 or acetone, which exhibits a seven-line spectrum at room temperature. This behavior contrasts with that associated with I11 and IV, which exhibit four-line ~pectra.~*~O Acknowledgment. We thank the Natural Sciences and Engineering Research Council of Canada for financial support for this study, including the purchase of the variable-temperature Faraday susceptometer and EPR spectrometer.

Correlation between 31P NMR data and structural parameters on Ag(PPh 3) 3X series. Crystal and molecular structure of tris(triphenylphosphine)silver(I)tetrafluoroborate and tris(triphenylphosphine)silver(I)iodide

The series Ag(PPh 3)3X, X=BF 4, NO 3, Cl and I, has been studied with 31P NMR spectroscopy. The crystal and molecular structures for X = BF 4 and I have been determined by X-ray diffraction. There are two independent molecules of the iodo com- plex in the asymmetric unit. Average values of both AgP bond distances and PAgP bond angles correlate with the 1 J( 107Ag– 31P) data. Three phosphorus atoms and one atom of the anion bind to the metal in a distorted tetrahedral arrangement which is modified by the coordination ability of the anion so that the system can be described as going from a tetrahedral to a trigonal geometry at the metal. A measure of the basicity of PPh 3 is given by comparing the coupling constant values in the p-tolyl- phosphine equivalent series of complexes Ag( p- tolyl) 3X. Selected structural data are: Ag—P bond distances = 2.577(3), 2.506(3) and 2.543(3) Å, AgF = 2.82(1) Å for the tetrafluoroborate complex whereas AgP bond lengths are 2.607(4), 2.572(4) and 2.585(4) Å in one molecule and 2.582- (4), 2.613(3) and 2.616(3) )Å in the other one, the AgI bond distances are 2.855(1) and 2.864(1) ) Å respectively. The bond angles around the metal are PAgP = 114.9(1)°, 119.3(1)° and 119.0(1)° for the tetrafluoroborate complex and 113.0(1)°, 113.2- (1)° and 113.2(1)° in the first molecule and 113.2- (1)°, 114.1(1)° and 110.8(1)° in the second one for the iodo complex respectively. By comparison with Cu analog complexes, out series shows larger average PMP bond angles, but unlike those complexes the metal-anion direction does not show threefold symmetry.

Kinetic and mechanistic aspects of the binding of dihydrogen by bis(ditertiaryphosphine)rhodium(I) tetrafluoroborate complexes, and activity of the dihydrides for catalytic asymmetric hydrogenation of prochiral olefinic acids

The kinetics of the reversible binding of H 2 by solutions of the cationic bis(ditertiaryphosphine)rhodium(I) complexes Rh(dppp) 2 + BF 4 − and Rh[(+)-diop] 2 + BF 4 −, where dppp = 1,3-bis(diphenylphosphino)propane and (+)-diop = 4 S,5 S-bis((diphenylphosphino)methyl)-2,2-dimethyl-1,3-dioxolane, are reported. Reversible formation of RhH 2dppp) 2 +, monitored by the stopped-flow method, analyzes for the expected second-order forward reaction opposed by a first-order off-rate. Formation of RhH 2(diop) 2 + proceeds, however, via a two-stage process which is interpreted in terms of intermediate solvated species containing monodentate diphosphine. Kinetic and spectroscopic studies on catalytic hydrogenation of the prochiral olefinic substrate, 2-methylenesuccinic acid, indicate a mechanism involving olefin coordination to the rapidly formed dihydride and subsequent hydrogen transfer; the (+)-diop system shows an unusual increase in optical yield of the R-2-methylsuccinic acid with temperature. Hydrogenation of olefinic acids with bis(diop) species is much slower than with comparable mono(diop) systems, but can lead to higher optical yields (e.g. up to 94% e.e. with ( Z)- N-acetamidocinnamic acid).

Mechanism of the cathode process in the electrolytic boriding in molten salts

The mechanism of the cathode process in the electrolytic deposition of boron on a platinum electrode has been investigated in the systems LiFKFKBF 4 and LiFKFB 2O 3 by means of the voltametric and chronopotentiometric methods. It was found that in the system LiFKFKBF 4 boron is reduced directly from the tetrafluoroborate complex anion by a simple 3-electron process. In the system LiFKFB 2O 3 boron oxide reacts with the basic fluoride electrolyte under formation of the BF − 4 anion and of unspecified oxofluoro complex(es) with a mean oxygen to boron ratio of 1.66. The ratio of boron concentrations in the BF − 4 anion and in the oxofluoro complex(es) is about 0.1. The difference between the deposition potential of boron from those two electrochemically active species is about 0.47 V in favour of BF − 4. The value of the diffusion coefficient of the BF − 4 anion was found to be 4.4 × 10 −9 m 2 s −1 (700°C).

Synthesis and magnetochemical. Spectroscopic, and structural studies of new tris(NN-dialkyldiselenocarbamato)iron(IV) tetrafluoroborate complexes

Four new [FeIV(Se2CNR2)3]+ Complexes [R = C2H5(1), R2N = morpholino (2), R2N = piperidino (3), and R = CH2C6H5(4)] have been prepared as BF4– salts, characterized by routine analytical and spectroscopic methods, and studied by variable-temperature magnetochemistry (100–300 K) and Mossbauer (120 K), e.s.r. (10–77 K), and X-ray photoelectron (300 K) spectroscopies. In addition, the molecular structure of (4) has been determined by X-ray crystallography with a= 33.213(18), b= 12.920(13), c= 10.748(10)A, β= 90.26(4)°, Z= 4 and shown to possess D3 macrosymmetry with the FeSe6 core having six selenium donor atoms at the apexes of a co-ordination polyhedron which is intermediate between the idealized trigonal prismatic and trigonal antiprismatic geometries. Overall, the present study indicates these tris-diselenocarbamate complexes to be low-spin iron(IV) species, similar to their tris-dithiocarbamate counterparts.

Phosphate, Phosphonate, and Phosphinate Complexes of Some Metal(II) Tetrafluoroborates

AbstractA number of anhydrous cobalt(II), nickel(II), and copper(II) tetrafluoroborate complexes of the ligands trimethyl phosphate, triethyl phosphate, triallyl phosphate, dimethyl methylphosphonate, diisopropyl methylphosphonate, dibutyl butylphosphonate and O,P‐dimethyl‐P‐phenylphosphinate have been prepared using a two step preparative procedure via the methanol complexes. For this type of ligand, this method gives better results than the usual one step procedure. The complexes are characterized with the aid of physical measurements such as ligand‐field spectroscopy.

ChemInform Abstract: NICKEL(II) COMPLEXES OF TRIMETHYLPHOSPHINE: CRYSTAL AND MOLECULAR STRUCTURE OF DIBROMOBIS(TRIMETHYLPHOSPHINE)NICKEL. COMPARISON WITH THE PENTACOORDINAT DIBROMOTRIS(TRIMETHYLPHOSPHINE)NICKEL AN BROMOTETRAKIS(TRIMETHYLPHOSPHINE)NICKEL TETRAFLUOROBORATE COMPLEXES

Chemischer InformationsdienstVolume 13, Issue 9 Physical Organic Chemistry ChemInform Abstract: NICKEL(II) COMPLEXES OF TRIMETHYLPHOSPHINE: CRYSTAL AND MOLECULAR STRUCTURE OF DIBROMOBIS(TRIMETHYLPHOSPHINE)NICKEL. COMPARISON WITH THE PENTACOORDINAT DIBROMOTRIS(TRIMETHYLPHOSPHINE)NICKEL AN BROMOTETRAKIS(TRIMETHYLPHOSPHINE)NICKEL TETRAFLUOROBORATE COMPLEXES A. MARI, A. MARISearch for more papers by this authorA. GLEIZES, A. GLEIZESSearch for more papers by this authorM. DARTIGUENAVE, M. DARTIGUENAVESearch for more papers by this authorY. DARTIGUENAVE, Y. DARTIGUENAVESearch for more papers by this author A. MARI, A. MARISearch for more papers by this authorA. GLEIZES, A. GLEIZESSearch for more papers by this authorM. DARTIGUENAVE, M. DARTIGUENAVESearch for more papers by this authorY. DARTIGUENAVE, Y. DARTIGUENAVESearch for more papers by this author First published: March 2, 1982 https://doi.org/10.1002/chin.198209059AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume13, Issue9March 2, 1982 RelatedInformation

Copper tetrafluoroborate complexes of the potentially binucleating ligand 1,4-di(2′-pyridyl)aminophthalazine. Mononuclear and polynuclear derivatives

Three different copper tetrafluoroborate complexes are obtained from the reaction of copper tetrafluoroborate and the title ligand (PAP) in water. Two crystalline modifications of a six-coordinate mononuclear protonated derivative, [Cu(PAPH)2(H2O)2](BF4)4, a triclinic brown form (I) and a monoclinic green form (II), and a dark green polynuclear complex containing neutral ligand and formulated as [Cu3(PAP)2(OH)2](BF4)(BF3OH)3•5H2O (III), are obtained from the same reaction mixture. The hydrolysis of BF4− in water is thought to be responsible for the formation of protonated PAP. In methanol a four-coordinate protonated derivative, [Cu(PAPH)2](BF4)4 (IV) and a binuclear complex [Cu2(PAP)2(H2O)2](BF4)4•0.5MeOH (V), containing neutral ligand, are obtained. The molecular structures of both forms of [Cu(PAPH)2(H2O)2](BF4)4 have been determined by single crystal X-ray diffraction. The brown triclinic form (I) belongs to space group [Formula: see text] with a = 9.856(1), b = 12.724(1), c = 9.401(1) Å, α = 101.691(8), β = 96.717(9), γ = 70.145(8)°, V = 1084.4 Å3, Z = 1. The green monoclinic form (II) belongs to space group P21/n with a = 12.663(4), b = 9.573(3), c = 18.813(4) Å, β = 107.16(2)°, V = 2178.9 Å3, Z = 2. Both complexes have tetragonally distorted six-coordinate structures involving axially bound water molecules and two in plane bidentate protonated ligands. The major difference between the structures involves the axial Cu—O(W) bond lengths (triclinic 2.497(9) Å; monoclinic 2.426(9) Å).

Determination of a Conformational Process in a Cesium Tetrafluoroborate Complex of 1,4,7,10,13,16-Hexaoxacyclooctadecane by Dynamic Nuclear Magnetic Resonance Spectroscopy.

Determination of a Conformational Process in a Cesium Tetrafluoroborate Complex of 1,4,7,10,13,16-Hexaoxacyclooctadecane by Dynamic Nuclear Magnetic Resonance Spectroscopy.

Synthesis and mechanism of formation of dicarbonyl(η4-trimethylenemethane)(η5-pentamethylcyclopentadienyl)molybdenum tetrafluoroborate

Reaction of [Mo(CO)3(η5-C5Me5)]BF4 generated from [Mo(CO)3(η5-C5Me5)]2 and AgBF4 with methylenecyclopropane, cis-, and trans-2,3-dimethylmethylenecyclopropanes affords dicarbonyl(η4-trimethylenemethane)(η5-pentamethylcyclopentadienyl)molybdenum tetrafluoroborate complexes, the stereochemistry of the reactions implicating a disrotatory ring-opening reaction.

Synthesis and reactions of η 5-C 5H 5Fe(CO) 2(acetylene) + BF 4− complexes

Zusammenfassung Dicarbonylcyclopentadienyliron(acetylene)-tetrafluoroborate complexes of diphenylacetylene and hexyne-3 have been isolated from the exchange reaction of the acetylene with CpFe(CO)2(isobutylene) tetrafluoroborate. With phenylacetylene the sole product formed in the exchange reaction is 2-phenylnaphthalene. Methyl propiolate yields the condensation products VI, VII and VIII.

ChemInform Abstract: COMPLEXES OF COBALT(II), NICKEL(II), AND COPPER ACETATES, PERCHLORATES, AND TETRAFLUOROBORATES WITH HETEROCYCLIC LIGANDS CONTAINING VA AND VIA GROUP DONOR ATOMS

AbstractDie Titelverbindungen (I) bis (IV) wurden durch Reaktion der Metallsalze mit Lösungen der Liganden in Chloroform oder Äthanol bzw. mit den Liganden in geschmolzener Form dargestellt.

Complexes of Cobalt(II), Nickel(II), And Copper Acetates, Perchlorates, and Tetrafluoroborates with Heterocyclic Ligands Containing Va and Via Group Donor Atoms

Cobalt(II), nickel(II), copper(II), and copper(I) acetate, perchlorate, and tetrafluoroborate complexes with thiazolidine-2-thione, thiomorpholin-3-one, and thiomorpholin-3-thione have been prepared. On the basis of infrared and far infrared spectra, electronic spectroscopy, magnetism, and molecular conductance, the stereochemistries of these complexes were identified. Assignments for the metal–ligand modes have also been made. By the use of infrared spectroscopy it has been possible to distinguish whether or not the polyanions present in the complexes are coordinated to the transition metal ion or are present as free ions. Spectroscopic parameters for the complexes have been calculated and compared with similar chromophores containing sulfur, oxygen, and nitrogen donor atoms.

Chelates of cupric salts with diethyl pyridine- and 4-methylpyridine-2-phosphonates

Synthetic and characterization studies of copper (II) perchlorate, nitrate and tetrafluoroborate complexes with diethyl pyridine-2-phosphonate (DEPP) and diethyl 4-methylpyridine-2-phosphonate (DEMPP) are reported. Complexes with the stoicheiometry Cu L 2 X 2 were generally obtained. DEPP and DEMPP act invariably as bidentate O,N-ligands in these complexes, coordinating through both the PO oxygen and the pyridine ring nitrogen. The Cu L 2 X 2 ( X  ClO 4, BF 4) chelates involve exclusively ionic ClO 4 or BF 4 groups and were formulated as [Cu L 2] X 2 with a square planar CuO 2N 2 moiety. The Cu(NO 3) 2 complexes are square pyramindal involving coordination of one monodentate nitrato group at the axial position: [Cu L 2(ONO 2)](NO 3). Electronic and i.r. spectral evidence suggests that DEMPP is a stronger ligand than DEPP.

Spectrophotometric determination of boron in glasses by extraction of Methylene Blue tetrafluoroborate complex

Spectrophotometric determination of boron in glasses by extraction of Methylene Blue tetrafluoroborate complex

Cobalt(II) complexes of pyradine

Pyridine complexes of cobalt(II) perchlorate, tetrafluoroborate, and nitrate have been prepared and studied by a variety of physical methods in both the solid and solution states. Their behavior is found to be generally similar to that of their nickel(II) analogues. The tetragonally distorted perchlorate and tetrafluoroborate, [Copy4X2], complexes contain coordinated anions in both the solid state and in dichloromethanepyridine solutions. Both are found to undergo extensive decomposition in nitromethane solutions. Addition of pyridine to such solutions produces species found to be different from that produced in the [Copy4(BF4)2]-pyridine system, which is probably [Copy6]2+. The nitrate complex, [Copy3(NO3)2], is thought to be monomeric in the solid state. It is shown to lose one mole of pyridine in dichloromethane and nitromethane solutions, forming [Copy2(NO3)2]. In dichloromethane-pyridine and nitromethane-pyridine solutions, the nitrate complex reacts with pyridine to form [Copy4(NO3)2] and [Copy5(NO3)]+ (or [Copy4(NO3)]+), respectively. No evidence is found for the existence of [Copy6]+ under these conditions. The tetrafluoroborate complex dissolves in pyridine to produce a species assumed to be [Copy6]2+, for which spectrochemical parameters are calculated.

Coordination compounds of olefins with anhydrous silver salts. IV. Complexes with some endocyclic monoolefins

A study has been made of the changes in the infrared and nuclear magnetic resonance (n.m.r.) spectra of cyclopentene, cyclohexene, cycloheptene, and cis-cyclooctene, and of their 1-methyl-substituted analogues upon formation of the silver tetrafluoroborate complexes, AgBF4•2olefin. Based on the perturbation of the double bond stretching frequency in the olefin, the order of decreasing strength of the silver ion – olefin interaction is cyclopentene > cyclohexene > cis-cyclooctene ≈ cycloheptene.