Premium
Kinetics of the Rapid Base Catalyzed Iodination of Imidazole and 2‐Methylimidazole by Molecular Iodine in Aqueous Medium: pH Effect
Author(s) -
Bonde S. L.,
Dangat V. T.,
Bhadane R. P.,
Joshi V. S.
Publication year - 2013
Publication title -
international journal of chemical kinetics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.341
H-Index - 68
eISSN - 1097-4601
pISSN - 0538-8066
DOI - 10.1002/kin.20770
Subject(s) - chemistry , imidazole , halogenation , catalysis , iodine , aqueous solution , base (topology) , kinetics , electrophile , inorganic chemistry , reactivity (psychology) , polymer chemistry , organic chemistry , medicine , mathematical analysis , physics , alternative medicine , mathematics , pathology , quantum mechanics
The second‐order kinetics of iodination of imidazole and 2‐methylimidazole in aqueous medium at various pH values and temperatures are studied in the presence and absence of a base catalyst. The reactions being electrophilic substitutions, molecular iodine is the sole iodinating agent, as the reactant solutions used are totally devoid of I − ions. The specific reaction rates of imidazole ( I ) and 2‐methylimidazole ( II ) for the catalyzed reactions are found to be 87.00 and 62.92 M −1 s −1 at 27.0°C, respectively, at 7.0 pH. The base component of the buffer used to maintain the pH catalyzes the reactions. The rapidity of the reactions necessitates the use of a rotating platinum electrode to follow the decay of the unreacted iodine. The study provides a quantitative verification of the reactivities of the substrates.