35280-47-8Relevant articles and documents
Modulation of electronic and redox properties in phenolate-rich cobalt(iii) complexes and their implications for catalytic proton reduction
Basu, Debashis,Allard, Marco M.,Xavier, Fernando R.,Heeg, Mary Jane,Schlegel, H. Bernhard,Verani, Claudio N.
, p. 3454 - 3466 (2015)
We investigate the redox, spectroscopy and catalytic reactivity of new cobalt(iii) complexes based on phenolate-rich [N2O3] ligands. These complexes are described as [CoIII(LX)MeOH], where X indicates the presence of chloro (1), bromo (2), iodo (3), or tert-butyl (4) substituents in the 3rd and 5th positions of each phenolate ring. These substituents modulate the Co(iii) ← PheO- LMCT bands of the parent complexes with 1 (451) > 2 (453) > 3 (456) > 4 (468 nm) and the redox potentials involved with the Co(iii)/Co(ii) and ligand reduction and with the phenolate/phenoxyl oxidation processes. The influence of the substituents on the phenolate pendant arms was also observed on the kinetic parameters; 1 presented a rate constant of 1.0 × 10-3 s-1 whereas 4 showed a considerably slower rate (5.3 × 10-5 s-1). Species 1 and 4 are electrocatalysts towards proton reduction in the presence of weak acid in acetonitrile. A TON of 10.8 was observed for 1 after 3 h of bulk electrolysis at -2.20 VFc/Fc+ using a mercury pool as the working electrode. This journal is
Kinetic Studies of the Methanolysis Reaction of Chloromethylated Phenols
Stein, Guenter,Boehmer, Volker,Lotz, Werner,Kaemmerer, Hermann
, p. 231 - 241 (2007/10/02)
The solvolysis of 25 differently substituted chloromethylated phenols was studied kinetically in methanol at 25 deg C.A sharp decrease of the initial reaction rate with increasing concentrations of added acids can be explained by a very fast solvolysis of the phenolate anions in comparison with the undissociated compounds.The latter show strictly first order kinetics up to high conversions and the rate constants can be partly correlated with the Jaffe relation.Highly negative values for the reaction constants ρ=-5.4 and ρ=-6.2 for ortho- and para-chloromethylated compounds show, that the undissociated phenols react according to the SN1-mechanism.However, deviations are found for compounds with strongly electron attracting substituents, which may be partly caused by an intramolecular catalytic effect of the phenolic hydroxy group in the case of the ortho-isomers. - Keywords: Methanolysis, Chloromethylated Phenols, Anchimeric Assistance
