Cobalt perchlorate, trans

Ci,Hi 6CI2C0N5O9, trans-Perchloratonitrosylbis(ethylenediamine)cobalt perchlorate, 42B, 715... 

The reaction between cerium(III) and cobalt(III). Part I. The perchlorates. Trans. Faraday Soc., 52, 1225-1234. 

With a view to determining the equilibrium constant for the isomerisation, the rates of reduction of an equilibrium mixture of cis- and rra/i5-Co(NH3)4(OH2)N3 with Fe have been measured by Haim S . At Fe concentrations above 1.5 X 10 M the reaction with Fe is too rapid for equilibrium to be established between cis and trans isomers, and two rates are observed. For Fe concentrations below 1 X lO M, however, equilibrium between cis and trans forms is maintained and only one rate is observed. Detailed analysis of the rate data yields the individual rate coefficients for the reduction of the trans and cis isomers by Fe (24 l.mole sec and 0.355 l.mole .sec ) as well as the rate coefficient and equilibrium constant for the cw to trans isomerisation (1.42 x 10 sec and 0.22, respectively). All these results apply at perchlorate concentrations of 0.50 M and at 25 °C. Rate coefficients for the reduction of various azidoammine-cobalt(lll) complexes are collected in Table 12. Haim discusses the implications of these results on the basis that all these systems make use of azide bridges. The effect of substitution in Co(III) by a non-bridging ligand is remarkable in terms of reactivity towards Fe . The order of reactivity, trans-Co(NH3)4(OH2)N3 + > rra/is-Co(NH3)4(N3)2" > Co(NH3)sN3 +, is at va-... 

The cationic aqua complexes of the C2-symmetric trans-chelating tridentate ligand 447 proved also highly effective chiral catalysts. The complexes involving the metal(II) perchlorates of iron, cobalt, nickel, copper and zinc produced the main endo adduct of cyclopentadiene and N - aery loy 1-1,3 -oxazo I i din -2 -one with very high ee values281. 

Other preparative methods have been reported.2,3 ds-Dibromobis(l, 2-ethane-diamine)cobalt(III) bromide is obtained in reasonable yield by evaporating a neutral aqueous solution of the trans isomer to dryness. The reaction between ds-diazidob is( 1,2-ethanediamine)cobalt(III) perchlorate and hydrobromic acid proceeds rapidly and quantitatively at ambient temperature, largely with retention of the cis configuration to yield the dibromo bromide.4,s The diazido starting complex6 7 can be made within 1 hour in greater than 90% yield. 

Linear and cyclic polyamine complexes of mthenium(III) have been little studied relative to those of first-row transition elements such as cobalt(III) and nickel(II), presumably due to a lack of general routes of syntheses. A convenient and reproducible method for the syntheses of trans-[RuLCl2], where L is any multidentate aliphatic ligand with a four-amine donor combination, has been developed. Procedures for the preparation of trans-[RuLCl2] [L = (en)2,J 2,3,2,-tet,f and cyclamj] are described here. The literature method is closely followed except that the much safer hexafluorophosphate(l — ) anion is employed in place of perchlorate. 

Ci,H, 6CI2C0N5O5, trans-Chloronitrosylbis ethylenediamine)cobalt (III) perchlorate, 35B, 588... 

C5H1gClCoNgOgS, trans-Bis(ethylenediamine)(isothiocyanato)-nitrito-cobalt(III) perchlorate, 45B, 1015... 

C12H2 6CIO2iRhg, trans-M3 Oxo-tris(bis(acetato)aquarhodium(III)) perchlorate monohydrate, 43B, 1234 Ci2H26MnOi6, Diaquabis(D-gluconato)manganese(II), 45B, 1112 C12H2 8CIC0N4O8, cis-anti-(Oxalatobis(2R,4S-diaminopentane)cobalt-... 

Cl2H16C1CoNs08 2 H2O, trans-Ammine-bis(L-histidinato)cobalt(III) perchlorate dihydrate, 45B, 1141... 

Cl6H3iCoNsNaOioS, Sodium trans-sulfitobis(dimethylglyoximato)-(aniline)cobaltate(lll) dihydrate, 44B, 994 Cl6H34CI2CUN4O10r (4,4,9,9-Tetramethyl-5,8-diazadodecane-2,11-dione bis(O-methyloxime))copper(II) perchlorate, 44B, 994 Cl8H36N4O4P4S4U, Tetraisothiocyanatotetrakis(trimethylphosphine ox-ide)uranium(lV), 45B, 1256... 

C20H3 2AS4CI3C0O1, trans-Dichlorobis- (o-phenylene(bisdimethy 1-arsine))cobalt(III) perchlorate, 35B, 869 C20H32AS4Cl3Ni, Dichlorobis(o-phenylenebis(dimethylarsine))nickel chloride, 38B, 1035... 

C2HH3 bASuCICoOs r ( + )-A-cis-p-((2,1 3-Dimethyl-6,9-diphenyl-2,6,9,13-tetraarsatetradecane)(dioxygen)cobalt(III)) perchlorate, 43B, 1438 C2 i,H3 9ClN2P2Pd, trans-Chloro-2-(phenylazo)phenylbis( triethylphos-phine)palladium(II), 35B, 842... 

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