Effect of Stabilizing Ligands on the Rate of Reaction of Cu^IL with CCl₃CO₂^- in Aqueous Solutions. 1. L = HOOCCHCHCOO^-

Abstract

The mechanism of the reaction of Cuaq + with Cl3CCOO- is reported; fumarate, which forms a complex with Cu(I), slows down the reaction rate considerably.

Copper(I) as a Homogeneous Catalyst for the Ullmann Reaction in Aqueous Solutions − The Transformation of 2-Bromobenzoate into Salicylate

“…Moreover, it formed a σ‐complex with Cu I and thus changed its redox potential favorably, but a reaction of Cu(NH 3 ) 2 + with a substrate requires a hybridization change probably from sp to sp 3 . Such a hybridization change is endothermic and was recently shown to decrease the rate of reaction of Cu I with CCl 3 CO 2 − 10…”

Ligand Effects on the Reactivity of CuIL Complexes Towards Cl3CCO2−

“…When N 2 O-saturated aqueous solutions at pH ϭ 3.0 containing 5.0·10 Ϫ2  CuSO 4 , 1.0  CH 3 OH, 2.0·10 Ϫ4  fumaric acid and (0.05Ϫ1.5)·10 Ϫ1  CH 3 CN are irradiated, all the primary radicals are transformed according reactions (7)Ϫ(11) to a mixture of Cu ϩ aq , Cu I (fumaric acid) and Cu I (CH 3 CN) n ϩ . [6,12] [13] …”

“…[6,11] The mixture of Cu ϩ aq , Cu I (HOOCCHϭCHCOO Ϫ ) (K ϭ 8.7·10 3  Ϫ1 at pH ϭ 3.0 [11] and Cu I (CH 3 CN) n ϩ thus reaches equilibrium within less than 50 µs after the pulse.…”

“…[6] The volume of activation was derived analogously to the method used for the reaction of Cu ϩ aq with O 2 . [9] The observed volume of activation ∆V 2 ϶ (Cu ϩ aq ) obs ϭ Ϫ9.9 Ϯ 1.0 mL/mol.…”

“…The effect of fumarate on the reaction of Cu ϩ aq with Cl 3 CCOO Ϫ (TCA) was recently [6] studied. The results demonstrate that the rate of reaction between Cu I -(HOOCCHϭCHCOO Ϫ ) and Cl 3 CCOO Ϫ is very slow.…”