Synthetic, structural, spectroscopic, and stopped-flow kinetic investigation of imine production


Baran Y., ÖZAY H., Esener H.

PROGRESS IN REACTION KINETICS AND MECHANISM, vol.36, no.2, pp.178-188, 2011 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 36 Issue: 2
  • Publication Date: 2011
  • Title of Journal : PROGRESS IN REACTION KINETICS AND MECHANISM
  • Page Numbers: pp.178-188

Abstract

Synthetic and formation kinetics studies have been made of imine production from the reaction of 3-methyl-2-thiophenecarboxyaldehyde with 3-(1H-imidazol-1-yl) propan-1-amine (L-1), 1-(3-aminopropyl) pyrolidin-2-one (L-2), 2-piperazin-1-ylethanamine (L-3) and 2-hydrazinopyridine (L-4). Kinetics were determined by rapid reaction techniques using absorbance changes at multi wavelengths in methanol. Activation enthalpies for imine formation in methanol vary from 101 to 121 kJ mol(-1) and entropies of activation (DS not equal) vary from -98 to -188 J K-1 mol(-1). All of these observations are indicative of an S(N)2 mechanism. Activation parameters of the reactions were calculated under second-order reaction conditions. The analysis of kinetic data in solutions was performed with the SPECFIT/32 software package which provides useful information on the binding characteristics of functional groups and mechanism of the reactions. The crystal structure of 3-methylthiophene-2-carbaldehyde pyridine-2-ylhydrazone is described.