Aquation

About: Aquation is a research topic. Over the lifetime, 1443 publications have been published within this topic receiving 17507 citations.

Kinetics of substitution at tris-(5-bromo-1,10-phenanthroline)-iron(II) and -iron(III)

Abstract: Rate constants are reported for several substitutions of the tris-5-bromo-1,10-phenanthroline (5-Brphen) complexes of iron(II) and of iron(III) These reactions include aquation in aqueous solution [iron(II) and iron(III)] and in several series of binary aqueous mixtures [iron(II) only], and reaction with hydroxide and with cyanide [iron(II) only] Reactivities are compared with those established fot analogous reactions of related complexes, and with thermodynamic parameters of the ligands and complexes

KINETICS OF AQUATION AND BASE HYDROLYSIS CIS BIOXALTOAMMINE BIS(ETHYLENEDIAMINE) COBALT(Ill) ION OF

Abstract: Cis bioxalatoammine bis (ethylenediamine) Co(Ill) cation has been synthesized and its aquation and base hydrolysis reactions have been investigated in 1.0 M NaCIO4 mediumIn the range of hydrogen ion concentration 0.02-1.0 M and temperature 55-70°C, the rate taw for the aquation of (enje(NH3) • CoC204H 2÷ is given by -d In (Complex)tot,l = (k 1 + kz(H ~ ))./(1 + KI,'(H+)) dt with k I (70°C) = 1.82 t-+ 0.10) × 10- ~ sec- 1, AH* = 26.9 ( + 1.6) kcal/mole and AS* = - 2.4 ( _+ 5) e.s.u. : k2(70°C)= 3.14(_+0.22) × 10 5sec-iM-i AH* = 24.0 ( _+1.7) kcal/mole and AS* = -9.71+Sje.s.u.; K t (70°C) = 3-0(_+0.5) x 10 2 M. The alkaline hydrolysis of (en)2(NH3)CoC20 ~ was studied at (OH-) < 0.1 M and in the temperature range 30-40°C. The rate law was found to be -d In (Complex),otal = k2 EO H -1, dt

Acid-Induced Aquation of (Trifluoromethyl)cobaloximes with Aromatic Nitrogenous Axial Ligands.

Abstract: CF 3 Co(D 2 H 2 )L ou (L=pyridine, methyl-1 imidazole et trimethyl-1,5,6 benzimidazole; D 2 H 2 =la dimethylglyoxime) ont ete prepares et caracterises par RMN de H1 et de F19. Cinetique de dissociation du coordinat axial en solution eau-acide sulfurique

Aquation of the Chloro Pentaammine Complexes of Cobalt(III) and Chromium(III): Do the Almost Equal Activation Parameters Arise from a Common Mechanism?

Abstract: The activation parameters for the aquation of Co(NH3)5Cl2+ and Cr(NH3)5Cl2+ are almost equal, and the strongly negative volumes of activation, ΔV⧧ (−9.9 and −10.6 cm3 mol-1 for Co and Cr, respectively), might at the first glance suggest a common associative mechanism for both complexes. Computations of the corresponding reaction coordinates indicate that, in agreement with Swaddle and co-workers' studies and as expected, a dissociative interchange mechanism (Id) operates for cobalt(III), but an associative interchange one (Ia) for chromium(III). For these two asymmetric reactions, the bond lengths changes δCo and δCr that are involved in the formation of the transition state and defined with respect to the fully concerted I pathway allow the attribution of the reaction mechanism. The signs of δCo and δCr, being positive and negative, suggest a d and a activation for the above aquations.