Kinetics of methylation of a solvatochromic vinylogous α‐pyridone in different solvents

The kinetics of the reaction with iodomethane of the solvatochromic dye 4‐2‐(N‐methyl‐4,6‐diphenylpyridiniumyl)]phenoxide 2, generated in situ from the corresponding N‐methyl‐2,4‐diphenyl‐6‐(4‐hydroxyphenyl)pyridinium salt 4, was studied in various solvents and solvent mixtures, in search of a possible correlation between its reactivity and solvatochromism in solution. © 1999 John Wiley & Sons, Inc. Int J Chem Kinet 31: 819–825, 1999