UNPRODUCTIVE SIGMA AND PI COMPLEXES IN THE REACTION OF 2-CHLOROQUINOXALINE WITH PIPERIDINE IN DIMETHYL SULPHOXIDE

Article abstract of DOI:10.1002/poc.610071004

The rate of the reaction of 2-chloroquinoxaline with piperidine in dimethyl sulphoxide was measured over a wide range of amine concentrations and at several temperatures.It was found that the order with respect to the nucleophile is close to 1 between 300 and 320 K, but is definitely less at lower and higher temperatures.It is suggested that below 300 K an unreactive charge-transfer complex is formed between the reactants which dissociates at higher temperatures, whereas at temperatures higher than 320 K an unproductive ? complex is formed, the concentration of which increases with increase in temperature.